Panasonic U-72MF2U9, U-96MF2U9, U-120MF2U9, U-144MF2U9, U-72MF2U94 service manual

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Page 1

U-72MF2U9 U-96MF2U9 U-120MF2U9 U-144MF2U9 U-72MF2U94 U-96MF2U94

Order No. SBPAC1509017CE

3WAY VRF System

U-120MF2U94 U-144MF2U94

Model No.

Outdoor Unit

Outdoor Unit TypeType

MF2 3WAY VRF System

 To be connecting Indoor Units

Indoor Units

Indoor Unit TypeType

U2 4-Way Cassette 36"x36"

4-Way Cassette 24"x24"

1-Way Cassette

Concealed Duct

-Medium Static Concealed Duct

-Low Static Concealed Duct

-High Static

Ceiling

Wall Mounted

Floor Standing

Concealed Floor Standing

S-07MD1U6

S-07MF2U6

S-07MM2U6

S-07MK2U6

S-07MP1U6

S-07MR1U6

Nominal Capacity

72 96 120 144

U-72MF2U9

U-72MF2U94

7 9 12 15 18 24 36 48 54

S-12MU2U6S-09MU2U6S-07MU2U6

S-09MY2U6S-07MY2U6

S-09MD1U6

S-09MF2U6

S-09MM2U6

S-09MK2U6

S-09MP1U6

S-09MR1U6

S-12MY2U6

S-12MD1U6

S-12MF2U6

S-12MM2U6

S-12MT2U6

S-12MK2U6

S-12MP1U6

S-12MR1U6

U-96MF2U9 U-120MF2U9 U-144MF2U9

U-96MF2U94 U-120MF2U94 U-144MF2U94

Nominal Capacity

S-15MF2U6

S-15MM2U6

S-15MP1U6

S-15MR1U6

S-18MY2U6

S-18MF2U6

S-18MM2U6

S-18MT2U6

S-18MK2U6

S-18MP1U6

S-18MR1U6

S-24MU2U6

S-24MF2U6

S-24MT2U6

S-24MK2U6

S-24MP1U6

S-24MR1U6

S-36MU2U6

S-36MF2U6

S-36ME1U6

S-48MF2U6 S-54MF2U6

S-48ME1U6

85464849346003

This air conditioner uses the refrigerant R410A.

REFERENCE NO.

SM830246-03

Page 2

•Donotleakrefrigerantwhilepipingworkforan installationorre-installation,andwhilerepairing refrigerationparts. Handleliquidrefrigerantcarefullyasitmaycause

frostbite.

When Servicing

•TurnthepowerOFFatthemainpowerbox(mains) beforeopeningtheunittocheckorrepairelectrical partsandwiring.

•Keepyourﬁngersandclothingawayfromanymoving parts.

•Cleanupthesiteafteryounish,rememberingto checkthatnometalscrapsorbitsofwiringhavebeen leftinsidetheunit.

WARNING



•Thisproductmustnotbemodiedor disassembledunderanycircumstances. Modiedordisassembledunitmaycausere, electricshockorinjury.

•Donotcleaninsidetheindoorandoutdoor unitsbyusers.Engageauthorizeddealeror specialistforcleaning.

•Incaseofmalfunctionofthisappliance,do notrepairbyyourself.Contacttothesales dealerorservicedealerforarepair.

CAUTION



•Donottouchtheairinletorthesharp

aluminumﬁnsoftheoutdoorunit.Yo u  maygetinjured.

• Ventilateanyenclosedareaswheninstallingor testingtherefrigerationsystem.Leaked refrigerantgas,oncontactwithﬁreorheat,can producedangerouslytoxicgas.

• Conrmafterinstallationthatnorefrigerantgas isleaking.Ifthegascomesincontactwitha burningstove,gaswaterheater,electricroom heaterorotherheatsource,itcancausethe generationoftoxicgas.

Others

CAUTION



•Donotsitorstepontheunit,youmay falldownaccidentally.

•Donottouchtheairinletorthesharp aluminumﬁnsoftheoutdoorunit. Yo u maygetinjured.

•DonotstickanyobjectintotheFA N  CASE. Yo u maybeinjuredandtheunitmay bedamaged.

Check of Density Limit

The room in which the air conditioner is to be installed requires a design that in the event of refrigerant gas leaking out, its density will not exceed a set limit.

Therefrigerant(R410A),whichisusedintheair conditioner,issafe,withoutthetoxicityorcombustibilityof ammonia,andisnotrestrictedbylawsimposedtoprotect theozonelayer.However,sinceitcontainsmorethanair, itposestheriskofsuffocationifitsdensityshouldrise excessively.Suffocationfromleakageofrefrigerantis almostnon-existent.Withtherecentincreaseinthe numberofhighdensitybuildings,however,theinstallation ofmultiairconditionersystemsisontheincrease becauseoftheneedforeffectiveuseofoorspace, individualcontrol,energyconservationbycurtailingheat andcarryingpower,etc. Mostimportantly,themultiairconditionersystemisable toreplenishalargeamountofrefrigerantcomparedto conventionalindividualairconditioners.

Ifasingleunitofthemultiairconditionersystemistobe installedinasmallroom,selectasuitablemodeland installationproceduresothatiftherefrigerant accidentallyleaksout,itsdensitydoesnotreachthelimit

(andintheeventofanemergency,measurescanbe madebeforeinjurycanoccur).

ASHRAEandtheInternationalMechanicalCodeofthe ICCaswellasCSAprovideguidanceanddeﬁne

safeguardsrelatedtotheuseofrefrigerants,allofwhich deﬁneaRefrigerantConcentrationLevel(RCL)of 400 oz

(11.3kg)per1,000ft3(28.3m

)for

R410Arefrigerant.

Foradditionalguidanceandprecautionsrelatedto refrigerantsafety,pleaserefertothefollowingdocuments:

InternationalMechanicalCode2012(IMC-2012) (ormorerecentlyrevised) ASHRAE15 ASHRAE34

IMPORTANT! Please Read Before Starting

This air conditioning system meets strict safety and operating standards. As the installer or service person, it is an important part of your job to install or service the

system so it operates safely and efﬁciently.

For safe installation and trouble-free operation, you must:

Carefully read this instruction booklet before beginning. Follow each installation or repair step exactly as shown. This air conditioner shall be installed in accordance with

National Wiring Regulations. Pay close attention to all warning and caution notices

given in this manual.

WARNING

CAUTION

If Necessary, Get Help

These instructions are all you need for most installation sites and maintenance conditions. If you require help for a special problem, contact our sales/service outlet or your certiﬁed dealer for additional instructions.

In Case of Improper Installation

The manufacturer shall in no way be responsible for improper installation or maintenance service, including

failure to follow the instructions in this document.

SPECIAL PRECAUTIONS

• Do not supply power to the unit until all wiring and tubing are completed or reconnected and checked.

• Highly dangerous electrical voltages are used in this system. Carefully refer to the wiring diagram and these instructions when wiring. Improper connections and inadequate grounding can cause accidental injury or death.

• Ground the unit following local electrical codes.

• Connect all wiring tightly. Loose wiring may cause over-

heating at connection points and a possible ﬁre hazard.

• To prevent possible hazards from insulation failure, the unit must be grounded.

• This equipment is strongly recommended to be installed with Earth Leakage Circuit Breaker (ELCB) or Residual Current Device (RCD). Otherwise, it may cause electrical shock and ﬁre in case of equipment breakdown or

insulation breakdown.

WARNING

ELECTRICAL SHOCK CAN CAUSE SEVERE PERSONAL INJURY OR DEATH. ONLY A QUALIFIED, EXPERIENCED ELECTRICIAN SHOULD ATTEMPT TO WIRE THIS SYSTEM.

This symbol refers to a hazard or unsafe practice which can result in severe personal injury or death.

This symbol refers to a hazard or unsafe practice which can result in personal injury or product or property damage.

When Wiring

When Transporting

Be careful when picking up and moving the indoor and outdoor units. Get a partner to help, and bend your knees when lifting to reduce strain on your back. Sharp edges or thin aluminum ﬁns on the air conditioner can cut your ﬁngers.

When Installing…

Select an installation location which is rigid and strong enough to support or hold the unit, and select a location for easy maintenance.

…In a Room

Properly insulate any tubing run inside a room to prevent “sweating” that can cause dripping and water damage to walls and ﬂoors.

…In Moist or Uneven Locations

Use a raised concrete pad or concrete blocks to provide a solid, level foundation for the outdoor unit. This prevents

water damage and abnormal vibration.

…In an Area with High Winds

Securely anchor the outdoor unit down with bolts and a metal frame. Provide a suitable air bafﬂe.

…In a Snowy Area (for Heat Pump-type Systems)

Install the outdoor unit on a raised platform that is higher than drifting snow. Provide snow vents.

When Connecting Refrigerant Tubing

• Pay particular attention to refrigerant leakages.

• Ventilate the room immediately, in the event that is

refrigerant gas leaks during the installation. Be careful not to allow contact of the refrigerant gas with a ﬂame as this will cause the generation of toxic gas.

• Keep all tubing runs as short as possible.

• Apply refrigerant lubricant to the matching surfaces of the

ﬂare and union tubes before connecting them, then tighten the nut with a torque wrench for a leak-free connection.

• Check carefully for leaks before starting the test run.

CAUTION

Keep the ﬁre alarm and the air outlet at least 5 ft. (1.5 m) away from the unit.

WARNING

• When performing piping work, do not mix air except for speciﬁed refrigerant (R410A) in refrigeration cycle. It causes capacity down, and risk of explosion and injury due to high tension

inside the refrigerant cycle.

• If the refrigerant comes in contact with a ﬂame, it produces a toxic gas.

• Do not add or replace refrigerant other than speciﬁed type. It may cause product damage, burst and injury, etc.

Page 3

frostbite.

When Servicing

•TurnthepowerOFFatthemainpowerbox(mains) beforeopeningtheunittocheckorrepairelectrical partsandwiring.

•Keepyourﬁngersandclothingawayfromanymoving parts.

•Cleanupthesiteafteryounish,rememberingto checkthatnometalscrapsorbitsofwiringhavebeen leftinsidetheunit.

CAUTION



•Donottouchtheairinletorthesharp

aluminumﬁnsoftheoutdoorunit.Yo u  maygetinjured.

WARNING



•Thisproductmustnotbemodiedor disassembledunderanycircumstances. Modiedordisassembledunitmaycausere, electricshockorinjury.

•Donotcleaninsidetheindoorandoutdoor unitsbyusers.Engageauthorizeddealeror specialistforcleaning.

•Incaseofmalfunctionofthisappliance,do notrepairbyyourself.Contacttothesales dealerorservicedealerforarepair.

Check of Density Limit

The room in which the air conditioner is to be installed requires a design that in the event of refrigerant gas leaking out, its density will not exceed a set limit.

Others

CAUTION



•Donotsitorstepontheunit,youmay falldownaccidentally.

•Donottouchtheairinletorthesharp aluminumﬁnsoftheoutdoorunit. Yo u maygetinjured.

•DonotstickanyobjectintotheFA N  CASE. Yo u maybeinjuredandtheunitmay bedamaged.

(andintheeventofanemergency,measurescanbe madebeforeinjurycanoccur).

ASHRAEandtheInternationalMechanicalCodeofthe ICCaswellasCSAprovideguidanceanddeﬁne

safeguardsrelatedtotheuseofrefrigerants,allofwhich deﬁneaRefrigerantConcentrationLevel(RCL)of 400 oz

(11.3kg)per1,000ft3(28.3m Foradditionalguidanceandprecautionsrelatedto

refrigerantsafety,pleaserefertothefollowingdocuments:

InternationalMechanicalCode2012(IMC-2012) (ormorerecentlyrevised) ASHRAE15 ASHRAE34

)for

R410Arefrigerant.

Page 4

3-2. Use R410A exclusive cylinder only.

Single-outlet valve

with the cylinder standing on end as shown.

New refrigerant R410A cannot be used for earlier models

1. Compressor specifications are different.

some of the materials used for compressor parts are different.

2. Existing tubing cannot be used (especially R22).

Completely cleaning out residual refrigerating

3. Refrigerating machine oil differs (R22).

Since R22 refrigerating machine oil is mineral oil, it does not dissolve in R410A. Therefore, refrigerating machine oil discharged from the compressor can cause compressor damage.

R22 refrigerating machine oil Mineral oil (Suniso oil)

R407C refrigerating machine oil Synthetic fluid (ether oil)

R410A refrigerating machine oil Synthetic fluid (ether oil)

Valve

Precautions for Installation Using New Refrigerant

1. Care regarding tubing

1-1. Process tubing

Material: Use clean, dry, free of oil, refrigeration grade, seamless, phosphorous deoxidized copper tube rated for R410A only. Wall thickness shall comply with the applicable legislation. The minimal wall thickness must be in accordance with the table below.

Tubing size: Be sure to use the sizes indicated in the table below.

Use a tube cutter when cutting the tubing, and be sure to remove any flash. This also applies to distribution joints (optional).

When bending tubing, use a bending radius that is 4 times the outer diameter of the tubing or larger.

Use sufficient care in handling the tubing. Seal the tubing ends with caps or tape to

CAUTION

prevent dirt, moisture, or other foreign substances from entering. These substances can result in system malfunction.

Outer diameter Wall thickness Outer diameter Wall thickness

5/8" (15.88) 0.040 (1.016) 1-5/8" (41.28) 0.060 (1.524)

3/4" (19.05) 0.042 (1.0668) Unit: in. (mm)

Material: O Material: O

1/4" (6.35) 0.025 (0.635) 7/8" (22.22) 0.045 (1.143)

3/8" (9.52) 0.030 (0.762) 1-1/8" (28.58) 0.050 (1.27)

1/2" (12.7) 0.035 (0.889) 1-3/8" (34.92) 0.055 (1.397)

1-2. Prevent impurities including water, dust and oxide from entering the tubing. Impurities can cause R410A

refrigerant deterioration and compressor defects. Due to the features of the refrigerant and refrigerating machine oil, the prevention of water and other impurities becomes more important than ever.

2. Be sure to recharge the refrigerant only in liquid form.

2-1. Since R410A is a non-azeotrope, recharging the refrigerant in gas form can lower performance and cause defects

in the unit.

2-2. Since refrigerant composition changes and performance decreases when gas leaks, collect the remaining

refrigerant and recharge the required total amount of new refrigerant after fixing the leak.

3. Different tools required

3-1. Tool specifications have been changed due to the characteristics of R410A. Some tools for R22- and R407C-type refrigerant systems cannot be used.

Item

Manifold gauge Yes No

Charge hose Yes No To resist higher pressure, material must be changed.

Vacuum pump Yes Yes

Leak detector Yes No

Flaring oil Yes No

* Using tools for R22 and R407C and new tools for R410A together can cause defects.

tools?

New

R407C tools

compatible

with R410A?

Remarks

Types of refrigerant, refrigerating machine oil, and pressure gauge are different.

Use a conventional vacuum pump if it is equipped with a check valve. If it has no check valve, purchase and attach a vacuum pump adapter.

Leak detectors for CFC and HCFC that react to chlorine do not function because R410A contains no chlorine. Leak detector for HFC134a can be used for R410A.

For systems that use R22, apply mineral oil (Suniso oil) to the flare nuts on the tubing to prevent refrigerant leakage. For machines that use R407C or R410A, apply synthetic oil (ether oil) to the flare nuts.

Manifold gauge

Vacuum pump

Outlet Inlet

iii

Page 5

3-2. Use R410A exclusive cylinder only.

New refrigerant R410A cannot be used for earlier models

1. Compressor specifications are different.

some of the materials used for compressor parts are different.

Valve

Single-outlet valve

with the cylinder standing on end as shown.

2. Existing tubing cannot be used (especially R22).

Completely cleaning out residual refrigerating

3. Refrigerating machine oil differs (R22).

Since R22 refrigerating machine oil is mineral oil, it does not dissolve in R410A. Therefore, refrigerating machine oil discharged from the compressor can cause compressor damage.

R22 refrigerating machine oil Mineral oil (Suniso oil)

R407C refrigerating machine oil Synthetic fluid (ether oil)

R410A refrigerating machine oil Synthetic fluid (ether oil)

Page 6

—

Section 1: CONTROL FUNCTIONS .......................................... 1-1

1. Introduction .............................................................1-2

2. Selecting Outdoor Unit for Operation .......................................... 1-3

3. Compressor Control .......................................................1-5

4. Output of PCB ..........................................................1-14

5. Outdoor Fan Control .....................................................1-20

6. Outdoor Unit CCU (command controller unit) Control ............................1-24

7. Tube Refrigerant Recovery Control ..........................................1-28

8. Oil Control .............................................................1-30

9. Defrost Control ..........................................................1-33

10. Discharge Tube Accumulated Refrigerant Recovery Control ....................... 1-39

11. Upper Current Limitation Mode (Demand control) ............................... 1-40

12. Backup Operation ....................................................... 1-42

13. Other Functions .........................................................1-46

14. Detailed Settings in EEPROM of Outdoor Unit .................................1-48

15. Outdoor Unit Control PCB .................................................1-50

Section 2: OUTDOOR UNIT REPAIR PROCEDURES ........................... 2-1

1. Removing Panels ......................................................... 2-2

2. Discharging Compressor Oil ................................................ 2-4

3. Backup Operation ........................................................ 2-7

4. Recovering Refrigerant .................................................... 2-9

5. Checking for Leakage After Repair .......................................... 2-14

6. Evacuating System ...................................................... 2-15

7. Charging Compressor Oil ................................................. 2-16

8. Pumping Out Refrigerant from Outdoot Unit ................................... 2-22

9. Compressor ........................................................... 2-26

10. Replacing Peripheral Parts of Fusible Plug .................................... 2-36

11. High and Low Pressure Sensors ............................................ 2-37

Section 3: OUTDOOR UNIT MAINTENANCE REMOTE CONTROLLER ............. 3-1

1. Overview ...............................................................3-2

2. Functions ...............................................................3-3

3. Ordinary Display Controls and Functions ...................................... 3-4

4. Monitoring Operations .....................................................3-9

5. Outdoor Unit Alarm History Monitor .......................................... 3-11

6. Mode Settings ..........................................................3-12

Section 4: REMOTE CONTROLLER FUNCTIONS ............................. 4-1

1. Simple Settings Function ................................................... 4-2

2. Detailed Settings Function .................................................. 4-8

3. Remote Controller Servicing Functions ....................................... 4-28

Page 7

Section 5: TROUBLE DIAGNOSIS .......................................... 5-1

1. Contents of Remote Controller Switch Alarm Display .............................5-2

2. Outdoor Unit Control Panel LED Display .......................................5-4

3. 3WAY Alarm Codes .......................................................5-5

4. Blinking Inspection Display on the Remote Controller ............................5-30

5. Inspection and Characteristics of Parts .......................................5-31

6. Test Pin ...............................................................5-35

7. Symptom: Thermostat in OFF continues or cycles OFF & ON too frequently ..........5-36

Section 6: TEST RUN .................................................... 6-1

1. Preparing for Test Run ..................................................... 6-2

2. Test Run Procedure ....................................................... 6-3

3. Main Outdoor Unit PCB Setting ..............................................6-4

4. Function Switches on P. C. Board ............................................6-7

5. Auto Address Setting ......................................................6-8

6. Setting Test Run Remote Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-16

7. Caution for Pump Down ................................................... 6-17

8. Self-Diagnosis Function Table and Contents of Alarm Display ..................... 6-17

Page 8

– MEMO –

vii

Page 9

3WAY VRF SYSTEM

2WAY VRF SYSTEM

Control Functions

Contents

Introduction .....................................................................................................................

1. 1-2

Selecting Outdoor Unit for Operation ...........................................................................

Compressor Control .......................................................................................................

Output of PCB ...............................................................................................................

Outdoor Fan Control .....................................................................................................

Outdoor Unit CCU (command controller unit) Control ..............................................

1. CONTROL FUNCTIONS

Control Functions

1-3

1-5

1-14

1-20

1-24

7. Tube Refrigerant Recovery Control .............................................................................

Oil Control ......................................................................................................................

Defrost Control ..............................................................................................................

Discharge Tube Accumulated Refrigerant Recovery Control ...................................

10.

Upper Current Limitation Mode (Demand control) .....................................................

11.

Backup Operation .........................................................................................................

12.

Other Functions ............................................................................................................

13.

Detailed Settings in EEPROM of Outdoor Unit ...........................................................

14.

Outdoor Unit Control PCB ............................................................................................

15.

1-28

1-30

1-33

1-39

1-40

1-42

1-46

1-48

1-50

1 - 1

Page 10

2WAY VRF SYSTEM

Control Functions

1. Introduction

2. Selecting Outdoor Unit for Operation

2-1. Outdoor Unit Operating Rules

As a result of setting the main outdoor and sub outdoor units due to the O/U.ADD setting, the order of priority for the outdoor units is determined in small values of O/U.ADD sequence. Because in this system all outdoor units contain an inverter compressor, ordinarily there is no absolute order of priority for compressor operation.

2-2. Delayed Start of Outdoor Units

2-2-1. Delayed start of outdoor unit in the same system

If it is necessary to operate the compressors simultaneously at multiple outdoor units, each outdoor unit will start in order of unit No. every one second, beginning with unit No. 1. *

Operation starts

Main outdoor unit Sub outdoor unit Sub outdoor unit

O/U.ADD = 1 O/U.ADD = 2 O/U.ADD = 3

Starts after 1 second Starts after 2 seconds Starts after 3 seconds

This is in order to reduce the load on the power supply equipment.

2-2-2. Delayed start for each system

When systems are linked with one communication cable and multiple systems are required to operate simultaneously by the central control device, all main outdoor units will begin operating simultaneously. In this situation, the load of the power supply equipment increases temporarily. To prevent the overload, the start timing of each system can be delayed. In order to enable this delay time, it must be set in the EEPROM for each system (Main outdoor unit). Those systems (Main outdoor units) where this setting has been made will start after a delay according to their system addresses. To activate this delay start function, it is necessary to set it to EEPROM on main outdoor PCB.

EEPROM setting in main outdoor unit

CODE: 3E

2WAY VRF SYSTEM

Control Functions

Delay timeSetting No.

(factory preset mode)

No delay start for each system

1 (System address × 1 × 8) seconds delay

2 (System address × 2 × 8) seconds delay

3 (System address × 3 × 8) seconds delay

3WAY VRF SYSTEM

1. Introduction

The MF2U series outdoor units for USA is a system that allows multiple outdoor units to be connected. All the outdoor units do not utilize the sub units that were used in earlier systems. The O/U.ADD of outdoor unit PCB where the unit is set to “1” becomes the main unit and activates as the CCU (command controller unit) functions that controls the entire system.

PCB Setting of Outdoor Unit

In order to determine the outdoor unit to be the main or sub unit, it is necessary to make settings at each PCB.

Main outdoor unit The outdoor unit where the O/U.ADD is set to “1” activates the CCU (command controller unit) functions that controls the entire system. This outdoor unit is the main outdoor unit.

* For the main outdoor unit, perform all the settings in the table (PCB setting of outdoor unit) below.

Sub outdoor unit The outdoor unit where the unit No. is set to other than “1” is a sub outdoor unit. * The system will not operate if outdoor units have been set other than unit No. “1”.

Control Functions

PCB Setting of Outdoor Unit

Factory

O/U.ADD [SW5] 11Outdoor units address

R.C.ADD [SW1, SW2] 1 Not necessarySystem 1 ~ 30System address

NO.OF I/U [SW3, SW4] 1 Not necessarySystem 1 ~ 52 unitsNo. of indoor units

NO.OF O/U 1 Not necessarySystem 1 ~ 3 unitsNo. of outdoor units[SW6]

* This system can be exteded to connect a maximum of 3 outdoor units.

preset

mode

Main outdoor unit

On-site setting

Sub outdoor unit

On-site setting

Setting other than 1

(Duplication prohibited)

1 - 2

Page 11

3WAY VRF SYSTEM

2. Selecting Outdoor Unit for Operation

2WAY VRF SYSTEM

Control Functions

2. Selecting Outdoor Unit for Operation

2-1. Outdoor Unit Operating Rules

2-2. Delayed Start of Outdoor Units

2-2-1. Delayed start of outdoor unit in the same system

If it is necessary to operate the compressors simultaneously at multiple outdoor units, each outdoor unit will start in order of unit No. every one second, beginning with unit No. 1. *

This is in order to reduce the load on the power supply equipment.

Control Functions

Operation starts

Main outdoor unit Sub outdoor unit Sub outdoor unit

O/U.ADD = 1 O/U.ADD = 2 O/U.ADD = 3

Starts after 1 second Starts after 2 seconds Starts after 3 seconds

2-2-2. Delayed start for each system

EEPROM setting in main outdoor unit

CODE: 3E

Delay timeSetting No.

(factory preset mode)

1 (System address × 1 × 8) seconds delay

2 (System address × 2 × 8) seconds delay

3 (System address × 3 × 8) seconds delay

No delay start for each system

1 - 3

Page 12

2. Selecting Outdoor Unit for Operation

3. Compressor Control

3-1. Compressors Mounted in the Outdoor Units

3-2. Compressor Selection Rules

Placement of compressor seen from the top

3-2-1. Priority order of compressors

Decide first priority order of compressor in each outdoor unit.

B. Priority order of compressor trip counter = 0 is higher than that of compressor trip counter = 1.

C. Inverter compressor: Shorter operating time > Longer operating time

D. Compressor that “outdoor unit small address”

installed in outdoor unit

Compressor that “outdoor unit large address” installed in outdoor unit

First priority order of inverter compressor in each outdoor unit > Other inverter compressor

Compressor trip counter =0 > Compressor trip counter =1

Shorter operating time > Longer operating time

“Outdoor unit small address”

installed in outdoor unit

“Outdoor unit large address” installed in outdoor unit

*1 Select first priority order of compressor in each outdoor unit by following method.

The compressor that has no trip counter, shorter operating time and smaller number of compressor will be taken first priority. First priority order of inverter compressor in each outdoor unit > Other inverter compressor

2WAY VRF SYSTEM

Control Functions

Type 120, 144

2nd compressor

1st compressor

Front side

Compressor trip counter =0 > Compressor trip counter =1

Shorter operating time > Longer operating time

1st compressor > 2nd compressor

Priority order flow of all compressors

Priority order flow of each outdoor unit

Type 72, 96

Front side

1st compressor

2-3. Outdoor Unit Stop Rules

2-3-1. Stopping of all outdoor units

When all outdoor units must stop, the units stop at the same time.

2-3-2. Stopping of individual outdoor units according to load of air-conditioning

● All cooling mode

3WAY VRF SYSTEM

Control Functions

Outdoor air temperature ≥ 113°F (45°C): All outdoor units will be operated. However, there is the outdoor unit which has the stopped compressor according to load of air-conditioning.

69.8°F (21°C) < outdoor air temperature < 113°F (45°C): the outdoor unit which has the compressor with the shortest amount of operating time continues to run and rest of the outdoor units may be stopped according to load air-conditioning. The outdoor unit which has any compressors without operation may be stopped. Outdoor air temperature ≤ 69.8°F (21°C): The outdoor unit which has the compressor with the shortest amount of operating time continues to run and rest of the outdoor units may be stopped according to load airconditioning. There is the outdoor unit which has only the operating compressor or uses only the heat exchanger with the stopped compressor according to some conditions.

● All heating mode The outdoor unit which has the compressor with the shortest amount of operating time continues to run and rest of the outdoor units may be stopped according to load air-conditioning.

● Mixed cooling/heating The outdoor unit which has the compressor with the shortest amount of operating time continues to run and rest of the outdoor units may be stopped according to load air-conditioning. There is the outdoor unit which has only the operating compressor or uses only the heat exchanger with the compressor stopped according to some conditions.

1 - 4

Page 13

3. Compressor Control

2WAY VRF SYSTEM

Control Functions

3-1. Compressors Mounted in the Outdoor Units

Placement of compressor seen from the top

Type 72, 96

3WAY VRF SYSTEM

Control Functions

Type 120, 144

1st compressor

Front side

3-2. Compressor Selection Rules

3-2-1. Priority order of compressors

Decide first priority order of compressor in each outdoor unit. The compressor that has no trip counter, shorter operating time and smaller number of compressor will be taken first priority. First priority order of inverter compressor in each outdoor unit > Other inverter compressor

B. Priority order of compressor trip counter = 0 is higher than that of compressor trip counter = 1.

C. Inverter compressor: Shorter operating time > Longer operating time

D. Compressor that “outdoor unit small address”

installed in outdoor unit

First priority order of inverter compressor in each outdoor unit > Other inverter compressor

Compressor trip counter =0 > Compressor trip counter =1

2nd compressor

Front side

Compressor that “outdoor unit large address”

installed in outdoor unit

Priority order flow of all compressors

1st compressor

*1 Select first priority order of compressor in each outdoor unit by following method.

“Outdoor unit small address”

Shorter operating time > Longer operating time

“Outdoor unit large address”

installed in outdoor unit

Priority order flow of each outdoor unit

Compressor trip counter =0 > Compressor trip counter =1

Shorter operating time > Longer operating time

1st compressor > 2nd compressor

installed in outdoor unit

1 - 5

Page 14

2WAY VRF SYSTEM

Control Functions

3. Compressor Control

3WAY VRF SYSTEM

3. Compressor Control

Control Functions

3-2-2. Operating compressors

When heat exchanger of the outdoor unit is condenser (All cooling mode or mixed cooling/heating) The compressor with higher priority order starts according to the priority order described on the compressor selection rules. Outdoor air temperature＜50°F (10°C): More than one compressor among all outdoor units will be operated.

When heat exchanger of the outdoor unit is evaporator (All cooling mode or mixed cooling/heating) At least, one inverter compressor operates when the system starts. The other compressors operate according to the priority order described on the compressor selection rules.

3-2-3. Stopping compressors

The compressor with lower priority order starts according to the priority order described on the compressor selection rules.

3-3. Operation When Starting 2 Compressors Mounted in Outdoor Unit

When necessary capacity gradually increases and one more inverter compressor is additionally started under the present operating compressor, reduce the compressor frequency to 25Hz temporarily and then start an additional compressor. The operation noted above is performed when 1st compressor or 2nd compressor is additionally started. If necessary capacity is initially higher and two compressors are started simultaneously, the operation noted above is not performed and both of them are regarded as the target frequency.

3-4. Operating Frequency Range of Inverter Compressor

The inverter compressor can operate within the range in the table below.

When the high pressure is over 435psi (3.0MPa), the upper limit frequency is 90Hz. If the high pressure is over 450psi (3.1MPa) and the minimum frequency operation is in progress, the system

is stopped. (P25: Pre-trip) If the low pressure is over 213psi (1.47MPa) during operation of the inverter compressor, the system is stopped.

(P27: Pre-trip) If 2 inverter compressors are simultaneously operating in the same outdoor unit, the frequency of 1st

compressor becomes 5Hz lower than that of 2nd compressor.

Type of outdoor unit

Minimum frequency (Hz)

Maximum frequency (Hz) 80

The frequency range in the table above is subject to change without notice.*

3-5. Forced Stopping of Compressor

Once a compressor stops, it will not start for a period of 3 minutes (3-minute forced OFF). However, this does not apply when the compressor was forced to stop as the result of a special control operation. (start control, defrost control, refrigerant oil recovery control, etc.)

72 96 120 144

15 15 15

100

1 - 6

Page 15

3WAY VRF SYSTEM

3. Compressor Control

3-6. Capacity Control (Roadmap control)

1 The capacity control by the compressors is performed according to the pressure sensor attached to the outdoor

unit and temperature thermistor attached to the indoor / outdoor unit heat exchanger. * With roadmap control, the pressure detected by the pressure sensor is converted to saturation temperature before it is used by microcomputer. This converted temperature is called “pressure sensor temperature”.

2 This control is performed every 30 seconds. 3 Required level of each indoor unit

Required level of indoor unit is calculated by difference between preset temperature in remote controller and intake temperature of indoor unit (TA), difference between preset discharge air temperature in EEPROM on indoor unit PCB and discharge air temperature of indoor unit (TF). Required level has “0” to “30” phases. This level becomes “31” at the test run. The target temperature of indoor unit heat exchanger is decided according to the maximum required level. * Target temperature of all indoor units heat exchanger is same value because all indoor units are connected with the same pressure piping.

4 Denition of evaporation temperature and condensation temperature

● Evaporation temperature (Te):

Shows the lowest temperature among the temperature sensors (E1 or E3) when the indoor unit heat exchanger is functioning as an evaporator. * When operating in mixed cooling/heating mode and the outdoor units are mixed evaporators, the outdoor unit

heat exchanger temperature is not recognized as “Te”.

● Condensation temperature (Tc): Shows the highest temperature among the high-pressure saturated temperature in the system and indoor unit heat exchanger’s liquid tube temperature (E1) with the thermostat ON.

Control Functions

3-6-1. Evaporation temperature adjustment by roadmap control The cooling capacity is adjusted with this control. It prevents freezing of the indoor unit's heat exchanger and the

dew to the outside panel of the indoor unit. The capacity is adjusted according to the following gure.

Evaporation temperature area

deg

Compressor capacity increase possible

43.0 (6.1)

42.8 (6.0)

37.4 (3.0)

37.2 (2.9)

* The evaporation temperature area changes depending on the maximum required level of each indoor unit as

shown above. * Area C is regarded as area B for 6 minutes after compressor starts. * When the system operates in a minimum capacity, the system will continue operating for at least 6 minutes if the

evaporation temperature area is area C. * The evaporation temperature is not adjusted while specially controlling defrosting and the oil recovery, etc. * The evaporation temperature is not adjusted when there are one or more indoor units that select the test run.

If one or more indoor units are selected into test run, the system doesn't stop in all states except alarm appearing.

* The test run will nish automatically in about one hour.

Compressor capacity increase prohibited

Compressor capacity decrease

60.8 (16.0)

55.4 (13.0)

Area A

Area B

Area C

51.8 (11.0)

46.4 (8.0)

Max. required level

unit: °F (°C)

42.8 (6.0)

37.4 (3.0)

1 - 7

Page 16

3WAY VRF SYSTEM

3. Compressor Control

3-6-2. Condensation temperature adjustment by roadmap control

The area B target temperature is different due to cooling, heating and mixed cooling/heating operation.

Target lower temperature

(Tc_tgt_min)

Cooling 127.4°F (53.0°C) 131.0°F (55.0°C)

Heating 118.4°F (48.0°C) 123.8°F (51.0°C)

Mixed cooling/heating 118.4°F (48.0°C) 123.8°F (51.0°C)

Cooling mode

The purpose of this control at cooling is to prevent abnormal high-pressure.

・Standard setting (at the shipment)

°F (°C) °F (°C)

PX=136.4

(58.0)

136.2

(57.9)

131.2

(55.1)

131.0

(55.0)

127.4

(53.0)

127.2

(52.9)

Thermostat OFF

Compressor capacity decrease

Compressor capacity increase prohibited

Compressor capacity increase possible

Area D

Area C

Area B

Area A

Heating mode and mixed cooling/heating mode

Heating capacity is adjusted with this control. It also prevents abnormal high-pressure simultaneously. The capacity is controlled in the following diagram.

PX=136.4

(58.0)

136.2 (57.9)

124.0 (51.1)

123.8 (51.0)

118.4 (48.0)

118.2 (47.9)

Target upper temperature

(Tc_tgt_max)

Thermostat OFF

Compressor capacity decrease

Compressor capacity increase prohibited

Compressor capacity increase possible

Area D

Area C

Area B

Area A

95.0

(35.0)

109.4 (43.0)

Control Functions

104.9 (40.5)

°F (°C)

123.8 (51.0)

118.4 (48.0)

91.4

(33.0)

15 300

Max. required level

* PX is usually xed to 136.4°F (58°C). If the high pressure goes up rapidly after the compressor starts, the system experiences urgent stop. The next time the system will start with lower PX. * In the area B, the compressor capacity changes depending on the refrigerant condition. * When the system operates in a minimum capacity, the system will continue operating for at least 6 minutes

if the condensation temperature area is area C.

* The condensation temperature is not adjusted when there are one or more indoor units that select the test run.

Limit pressure adjustment function

Operation pressure is able to be adjusted for existing old piping. If area shift function is set, values below shift. EEPROM setting in main outdoor unit CODE : 4B

Setting No. Limited pressure PX °F (°C) Cooling mode

Tc_tgt_min Tc_tgt_max Tc_tgt_min Tc_tgt_max 0 478.5psi (3.3MPa) 126.5 (52.5) 116.6 (47.0) 120.2 (49.0) 116.6 (47.0) 118.4 (48.0) 1 No use - - - - 2 551.1psi (3.8MPa) 136.4 (58.0) 127.4 (53.0) 131.0 (55.0) 118.4 (48.0) 123.8 (51.0) 3 No use - - - - -

Heating mode and mixed

cooling/heating mode

1 - 8

Page 17

3WAY VRF SYSTEM

3. Compressor Control

3-6-3. Cooling operation with low ambient temperature

When operating in cooling mode with the ambient temperature less than 69.8°F (21°C), the unit is set in low ambient temperature cooling mode. During low ambient temperature cooling mode, the heat exchanger capacity control is performed in addition to the compressor capacity control. The target condensation temperature (Tc_tgt) is controlled between 73.4°F ~ 77°F (23°C ~ 25°C). Thereof, the heat exchanger may sometimes be used by half even if the operation is cooling in all indoor units.

(1) Capacity changes of compressor Similar to control normal cooling operation (2) Capacity changes of heat exchanger * Condensation temperature (Tc) is high

The outdoor heat exchanger capacity is increased, increasing the system condensation capacity and lowering the condensation temperature (Tc).

* Condensation temperature (Tc) is low

The outdoor heat exchanger capacity is decreased, decreasing the system condensation capacity and raising the condensation temperature (Tc).

Outdoor Unit Heat Exchanger Control Table

Low　　　 ← Condensation Temp. [Tc] → High

A C

B D

Control Functions

91.4°F

87.8°F

(31°C)

83.3°F

(28.5°C)

57.2°F (14°C)

51.8°F (11°C)

42.8°F (6°C)

37.4°F (3°C)

26.6°F (-3°C)

Low←Evaporation Temp. [ Te ]→High

3-6-4. Control of condensation temperature and evaporation temperature during mixed cooling/heating operation

During mixed cooling/heating operation, the control maintains a heat balance with a target evaporation temperature (Te) for the cooling mode indoor units of 37.4°F ~ 42.8°F (3°C ~ 6°C) and a target condensation temperature (Tc) for the heating mode indoor units of 118.4°F ~ 123.8°F (48°C ~ 51°C). Heat balance control is performed by varying the compressor capacity and heat discharge (heat intake) of the heat exchanger.

(1) Increasing/decreasing the compressor capacity

* When evaporation temperature (Te) is high and condensation temperature (Tc) is low.

This occurs when both the cooling capacity (heat intake) and the heating capacity (heat discharge) are low.

The compressor capacity and the circulation ow of refrigerant are increased in order to lower the evaporation

temperature (Te) and raise the condensation temperature (Tc).

* When evaporation temperature (Te) is low and condensation temperature (Tc) is high

This occurs when both the cooling capacity (heat intake) and the heating capacity (heat discharge) are high.

The compressor capacity and the circulation ow of refrigerant are decreased in order to raise the evaporation

temperature (Te) and lower the condensation temperature (Tc).

* Under conditions other than those listed above, the capacity of the outdoor unit heat exchanger is adjusted.

In some cases the heat exchanger capacity may also be adjusted at the same time when the compressor capacity is varied.

89.6°F

(32°C)

(33°C)

95°F

1 - 9

(35°C)

100.58°F

100.4°F

(38°C)

(38.1°C)

101.48°F

UPDOWN STAY

136.4°F

(38.6°C)

(58°C)

Compressor stop

Page 18

Compressor Control Table

ABCD

3. Compressor Control

Low Condensation Temp. [Tc] High

3WAY VRF SYSTEM

Control Functions

C not_UP

Low Evaporation Temp. [Te] High

Evaporation temperature (Te) and condensation temperature (Tc) areas A, B, C and D are the same as for evaporation temperature control and condensation temperature control.

(2) Increasing/decreasing the heat exchanger capacity (when the outdoor unit heat exchanger is functioning as a condenser)

• Primarily when both the evaporation temperature (Te) and condensation temperature (Tc) are high This occurs when the cooling capacity (heat intake) is low and the heating capacity (heat discharge) is high. The outdoor heat exchanger capacity is increased, increasing the system condensation capacity and lowering the condensation temperature (Tc). The amount of heat discharge at the outdoor unit heat exchanger is increased, increasing the heat intake at the cooling mode indoor units and lowering the evaporation temperature (Te).

• Primarily when both the evaporation temperature (Te) and condensation temperature (Tc) are low This occurs when the cooling capacity (heat intake) is high and the heating capacity (heat discharge) is low. The outdoor heat exchanger capacity is decreased, decreasing the system condensation capacity and raising the condensation temperature (Tc). The amount of heat discharge at the outdoor unit heat exchanger is decreased, decreasing the heat intake at the cooling mode indoor units and raising the evaporation temperature (Te).

slow_UP Target

not_UP

STOP

DOWN

Outdoor Unit Heat Exchanger Control Table (when the outdoor unit heat exchanger is functioning as a condenser)

42.8°F (6°C)

37.4°F (3°C)

26.6°F (-3°C)

Low←Evaporation Temp. [ Te ]→High

32°F (0°C)

Low　　　 ← Condensation Temp. [Tc] → High

A C

110.3°F

(43.5°C)

114.8°F

(46°C)

STAY

DOWN

B D

123.8°F

(51°C)

118.4°F

(48°C)

Target

1 - 10

136.4°F

(58°C)

Compressor stop

Page 19

3WAY VRF SYSTEM

3. Compressor Control

(3) Increasing/decreasing the heat exchanger capacity (when the outdoor unit heat exchanger is functioning as an evaporator)

• Primarily when both the evaporation temperature (Te) and condensation temperature (Tc) are low This occurs when the cooling capacity (heat intake) is high and the heating capacity (heat discharge) is low. The outdoor heat exchanger capacity is increased, increasing the system evaporation capacity and raising the evaporation temperature (Te). The amount of heat intake at the outdoor unit heat exchanger is increased, increasing the heat discharge at the heating mode indoor units and raising the condensation temperature (Tc).

• Primarily when both the evaporation temperature (Te) and condensation temperature (Tc) are high This occurs when the cooling capacity (heat intake) is low and the heating capacity (heat discharge) is high. The outdoor heat exchanger capacity is decreased, decreasing the system evaporation capacity and lowering the evaporation temperature (Te). The amount of heat intake at the outdoor unit heat exchanger is decreased, decreasing the heat discharge at the heating mode indoor units and lowering the condensation temperature (Tc).

Outdoor Heat Exchanger Control Table (when the outdoor heat exchanger is functioning as an evaporator)

Low　　　 ← Condensation Temp. [Tc] → High

A C

B D

127.4°F

(53°C)

129.2°F

(54°C)

130.1°F

118.4°F

(48°C)

123.8°F

(51°C)

(54.5°C)

Control Functions

136.4°F

(58°C)

42.8°F (6°C)

37.4°F (3°C)

STAY

30.2°F (-1°C)

26.6°F (-3°C)

24.8°F (-4°C)

Low←Evaporation Temp. [ Te ]→High

DOWN

Target

STA Y

Compressor stop

3-7. Protection Control

3-7-1. Compressor discharge temperature protection

The compressor capacity is controlled according to the table below. *Discharge temperature that is used for this control is the highest temperature among all compressors.

Discharge temp.

°F (°C)

222.8

(106)

221.0 (105)

219.2 (104)

217.4 (103)

213.8 (101)

3-7-2. Abnormal low pressure protection

The compressor capacity is controlled according to the table below.

Low pressure

psi (MPa)

36.3 (0.25)

29.0 (0.20)

24.7 (0.17)

Stop

If this temperature is detected at regular intervals, alarm appears.

Compressor capacity decrease

Compressor capacity increase prohibited

Compressor capacity increase possible

No restriction

Capacity goes up slowly

Capacity increase prohibited

Capacity goes down

Capacity goes down 2.0 hp

Capacity goes down 1.0 hp

Capacity goes down 0.5 hp

1 - 11

hp = horsepower

Page 20

2WAY VRF SYSTEM

Control Functions

3. Compressor Control

2WAY VRF SYSTEM

Control Functions

3. Compressor Control

Inverter layout

Noise

filter

R S T

Power

supply

Primary CT1

Primary CT2

Secondary CT1

Secondary CT2

Diode bridge

IPM (CM)

1st compressor

Fan motor

U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94

Use the same values of 1st compressor and 2nd compressor.

unit: Ampere

Current limit 1

Maximum current 1 H

Primary

Maximum current 1 L 15.5

19.5 19.5 19.5 19.5

72 96 120 144

15.5

16.5

15.5

16.5 16.5 16.5

15.5

Current limit 2

Maximum current 2 H

Secondary

Maximum current 2 L 13.1

16.6 23.0 16.6 16.6

19.5

14.1

13.1

14.1 20.5 14.1

13.1

Type of outdoor unit

Noise

filter

Diode bridge

IPM (CM)

IPM (FN)

2nd compressor

3. Compressor Control

3-7-3. Current protection

This restriction protects the compressor and controls the compressor electric current simultaneously. The current limitation value changes to “normal status” and “overload status” according to the outdoor temperature. The primary and secondary current values of 1st compressor and 2nd compressor are measured.

3WAY VRF SYSTEM

Control Functions

Outdoor temperature

U-72MF2U9 / U-96MF2U9 / U-120MF2U9 / U-144MF2U9

A Normal status: Use the same values of 1st compressor and 2nd compressor.

Primary

Secondary

Overload status: Use the same values of 1st compressor and 2nd compressor.

114.8°F (46°C)

Type of outdoor unit

Current limit 1

Maximum current 1 H

Maximum current 1 L24

Current limit 2

Maximum current 2 H

Maximum current 2 L24

Current limit 1

Current table <Overload>

Current table <Normal>

72 96 120 144

30 43 30 30

25 38 22.5

30 44 30 30

25 40 25

72 96 120 144

30 43 30 30

22.5

21.5

Outdoor temperature

109.4°F (43°C)

unit: Ampere

Primary

Secondary

Inverter layout

Power

supply

R S T

Maximum current 1 H

Maximum current 1 L24

Current limit 2

Maximum current 2 H

Maximum current 2 L24

Noise

filter

Primary CT1

Primary CT2

filter

25 38 21

30 44 30 30

25 40 23

Diode bridge

IPM (CM)

IPM (FN)

IPM (CM)

Secondary CT1

1st compressor

Fan motor

Secondary CT2

2nd compressor

1 - 12

Page 21

2WAY VRF SYSTEM

Control Functions

3. Compressor Control

U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94

Use the same values of 1st compressor and 2nd compressor.

Type of outdoor unit

Current limit 1

72 96 120 144

19.5 19.5 19.5 19.5

3WAY VRF SYSTEM

Control Functions

unit: Ampere

Primary

Secondary

Inverter layout

Power

supply

S T

Maximum current 1 H

Maximum current 1 L 15.5

Current limit 2

Maximum current 2 H

Maximum current 2 L 13.1

Noise

filter

Primary CT1

Noise

filter

16.5 16.5 16.5

16.6 23.0 16.6 16.6

14.1 20.5 14.1

Diode

bridge

Diode

bridge

15.5

19.5

16.5

15.5

14.1

13.1

15.5

13.1

IPM (CM)

IPM (FN)

IPM (CM)

Secondary CT1

1st compressor

Fan motor

Secondary CT2

2nd compressor

Primary CT2

1 - 13

Page 22

4. Output of PCB

Item Indication on PCB

Solenoid valve

Expansion valve

Crankcase heater

3WAY VRF SYSTEM

Control Functions

Discharge valve 1 DCV1 Discharge valve 2 DCV2 Suction valve 1 SCV1 Suction valve 2 SCV2 Heat exchanger pressure balance valve 1 PBV1 Heat exchanger pressure balance valve 2 PBV2 Save valve SAVE Refrigerant control valve RCV Refrigerant balance valve RBV Oil recovery valve ORVR By-pass valve BPV Accumulator valve ACV

valve O2 MOV for heat exchanger 1 MOV1 MOV for heat exchanger 2 MOV2 SC circuit expansion valve MOV4 Crankcase heater control 1 CH1 Crankcase heater control 2 CH2

4-1. [DCV, SCV, PBV]

Turn DCV, SCV and PBV to ON/OFF. Change the outdoor unit heat exchanger mode and/or control the heat exchanger capacity. See the basic operation listed below.

All

cooling

mode

All

heating

mode

Mixed

cooling/

heating

mode

Status of

heat exchanger

Normal Condenser ON ON OFF OFF OFF OFF

Low ambient temperature

System stopped

Other outdoor *2 units operating

Heat exchanger [condenser] of outdoor unit

Heat exchanger [evaporator] of outdoor unit

Condenser ON/OFF ON OFF OFF OFF OFF

Stop OFF OFF OFF OFF OFF OFF

Evaporator ON ON ON ON ON ON

Stop OFF OFF OFF OFF OFF OFF

Stop ON ON ON ON ON ON

Condenser ON/OFF ON OFF OFF OFF OFF

Stop OFF OFF OFF OFF OFF OFF

Evaporator ON/OFF ON ON/OFF ON ON/OFF ON

Stop OFF OFF OFF OFF OFF OFF

DCV1

DCV2 SCV1

SCV2 PBV1

PBV2

*1 The system which is stopped in heating mode shows the status of all outdoor units stopped. *2 When other outdoor units are operating in heating mode, the outdoor unit in stop mode is holding the pulse at 0 pulses of MOV1 and MOV2 in a situation in which the heat exchanger is evaporator. *3 DCV1, SCV1 and PBV1 turn ON/OFF respectively due to the capacity control of the heat exchanger.

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Page 23

3WAY VRF SYSTEM

4. Output of PCB

4-2. Save Valve [SAVE]

● This valve turns ON for 5 seconds before the inverter compressor starts. After the inverter compressor starts, the valve turns ON for 10 seconds. Then it turns OFF.

● This valve turns ON for 30 seconds after the outdoor unit stops. Then it turns OFF.

● This valve turns ON when high pressure sensor detects 496psi (3.42MPa) to prevent abnormal pressure. This valve turns OFF when the high pressure goes down below 481.5psi (3.32MPa).

● This valve might turn ON when the system capacity is excessive although the inverter compressor operates at

Min. frequency.

● This valve turns ON in the following status : (Compressor discharge temperature - High pressure saturation temperature) < 9deg F (5deg C)

● Under control of Tube Refrigerant Recovery Control

● Under control of heat exchanger select mode

● This valve turns ON when low pressure sensor goes down 24.7psi (0.17MPa) to prevent abnormal pressure. This valve turns OFF when low pressure sensor increase 29psi (0.20MPa) or over.

4-3. Refrigerant Control Valve [RCV]

The main purpose of this valve is to detect the ow of refrigerant (refrigerant volume) on the indoor unit when the

outdoor unit heat exchanger is functioning as a condenser. When the valve determines that there are signs of a low refrigerant level, refrigerant is supplied from the receiver tank to the system.

● This valve turns ON when the evaporator is refrigerant shortage. The heat exchanger of indoor unit is evaporator in cooling operation. The heat exchanger of outdoor unit is evaporator in heating operation.

● This valve turns OFF when the excessive refrigerant is in the condenser. The heat exchanger of indoor unit is condenser in heating operation. The heat exchanger of outdoor unit is condenser in cooling operation.

● This valve turns OFF when the outdoor unit is stopped.

● This valve turns ON at stopped outdoor units when the heat exchanger at another outdoor unit is functioning as a condenser.

Control Functions

RCV

RBV

RCV

RBV

Evaporator

Two-phase

flow

Refrigerant shortage in evaporator

Receiver tank holds refrigerant

Evaporator

Two-phase flow

Sufficient refrigerant is supplied to evaporator

High pressure from RCV pushes the liquid refrigerant out of the receiver tank

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Page 24

3WAY VRF SYSTEM

4. Output of PCB

4-4. Refrigerant Balance Valve [RBV]

The main purpose of this valve is to detect the ow of refrigerant (refrigerant volume) on the indoor unit when the

outdoor unit heat exchanger is functioning as an evaporator. When the valve determines that there are signs of excess refrigerant, refrigerant is recovered at the receiver tank. This valve is ON during heating operation and when the outdoor unit heat exchanger is functioning as an evaporator during mixed heating/cooling operation. It also turns ON in order to recover refrigerant at the outdoor unit after heating operation is stopped. * This valve is never ON at the same time as the RCV.

● This valve turns ON for 20 seconds after the system stops at heating mode, and then turns OFF.

● This valve turns ON once after the system starts at heating mode.

● This valve turns OFF when an abnormal drop in compressor discharge gas temperature is detected.

● This valve turns OFF when liquid back to the compressor is occurring. Judgment of liquid back: Detected suction temperature is lower than low-pressure sensor temperature. Difference between high-pressure sensor temperature and discharge temperature of compressor is small. (less than 9deg F (5deg C))

* After the valve turns from ON to OFF, it will not turn ON again for 15 minutes.

● This valve turns ON when low pressure sensor decreases 24.7psi (0.17MPa) at stopped system. This valve turns OFF when low pressure sensor increases 29psi (0.20MPa).

Two-phase flow

RCV

Condenser

Control Functions

RBV

Receiver tank holds small amount of refrigerant

Liquid flow

RCV

RBV

Refrigerant gas in the top of receiver tank is pulled into low pressure side.

4-5. Oil Recovery Valve [ORVR]

This valve is for recovering oil from the oil separator of its own outdoor unit or balance tube to the compressor of its own outdoor unit.

● This valve turns ON when the oil level of the compressor is “0” or “1”. In this situation, system performs Self oil recovery control, Inter-outdoor unit oil recovery control, or system oil recovery control.

● This valve turns ON for 2 minutes after the compressor starts.

● This valve is always OFF when outdoor unit is stopped.

* For oil level of compressor, see “Oil Control” section.

Liquid

flow

Over charge condition

Condenser

Two-phase flow

Adequate condition

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Page 25

3WAY VRF SYSTEM

4. Output of PCB

4-6. By-Pass Valve [BPV]

This valve is for pushing the oil in the balance piping into other outdoor unit.

● This valve turns ON when the oil level of compressor is “2” or “1” in its own outdoor unit and the oil level of compressor is “0” in other outdoor unit. * This valve turns ON for 10 seconds and turns OFF for 20 seconds. This operation is repeated while oil is

supplied to others.

* For more information on oil level of compressor, see “Oil Control” section.

4-7. Accumulator Valve [ACV]

The purpose of this valve is to recover oil and refrigerant from the accumulator to the compressor.

● This valve turns OFF when the compressor operation just started.

● This valve turns ON when the compressor is warmed up.

● This valve turns ON while the oil recovery among the systems and defrost control are in progress.

● This valve turns ON while the MOV4 is operating.

Control Functions

4-8. O2 Valve [O2*]

This valve works when the outdoor unit receives signal of the refrigerant leakage from the indoor unit. The indoor unit that transmits the signal of the refrigerant leakage gives “P14”alarm. To activate this function, it is necessary to set it to EEPROM on the main outdoor PCB and indoor PCB.

EEPROM setting in main noutdoor unit

CODE: C1

Setting No.

0 This function invalid (factory preset mode)

EEPROM setting in indoor unit

CODE: 0B

Setting No.

0 Function of EXCT plug short-circuit

1 Indoor unit gives “P14”alarm and transmits the refrigerant leakage signal.

4-9. MOV for Heat Exchanger [MOV1, MOV2]

4-9-1. Type of expansion valves

This valve is turned OFF when the system is normal. This valve is turned ON when the outdoor unit receives signal from the indoor unit.

This valve is turned ON when the system is normal. This valve is turned OFF when the outdoor unit receives signal from the indoor unit.

MOV1 For upper side heat exchanger

MOV2 For lower side heat exchanger

*O2 valve is the eld supply parts.

4-9-2. Power Initialization If no indoor units have started (even once) after the power supply to the outdoor unit, the MOV for heat exchanger

holds the pulse at 480 pulses.

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Page 26

3WAY VRF SYSTEM

4. Output of PCB

4-9-3. Expansion valves for heat exchanger control

The conguration of the heat exchangers is different depending on the capacity of the outdoor unit.

Operation of electronic control valves during normal unit operation

All

cooling

mode

Status of

heat exchanger

Normal Condenser 480 480 Maximum ow control

Low ambient temperature

Condenser 0 ~ 480 0 ~ 480 Heat exchanger capacity control

Stop 0 0 Refrigerant shut-off

MOV1 MOV2 Remarks

Control Functions

Evaporator 12 ~ 480 12 ~ 480 SH control

All

heating

mode

Mixed cooling/ heating

mode

When operating in all cooling or all heating mode, the heat exchangers of which the compressors are driving in the outdoor units are used. However, when operating in cooling mode with low ambient temperature, the number of pieces for using the heat exchanger is changed according to the operating condition of indoor units and the status of outdoor units. When operating in mixed cooling/heating mode, the condition and the number of pieces for using the heat exchanger are changed according to the operating condition of indoor units and the status of outdoor units. The heat exchanger is selected in turn from the outdoor unit 2nd heat exchanger as the shortest operating time of the inverter compressor. SH control is controlled so that the difference of temperature between the liquid tube temperature and gas tube temperature should be set within the range as shown below.

Mixed cooling/heating mode (Heat exchanger [evaporator] of outdoor unit) 3.6deg F ~ 9deg F (2deg C ~ 5deg C)

System stopped Stop 0 0 Refrigerant shut-off

Other outdoor units operating

Heat exchanger [condenser] of outdoor unit

Heat exchanger [evaporator] of outdoor unit

Stop 0 0 Refrigerant shut-off

Condenser 0 ~ 480 0 ~ 480 Heat exchanger capacity control

Stop 0 0 Refrigerant shut-off

Evaporator 12 ~ 480 12 ~ 480 SH control

Stop 0 0 Refrigerant shut-off

Outdoor unit Capacity Target value of SH control

All heating mode -1.8deg F ~ 9deg F (-1deg C ~ 5deg C)

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Page 27

3WAY VRF SYSTEM

4. Output of PCB

4-10. SC Circuit Expansion Valve [MOV4]

4-10-1. SC control (Cooling mode only)

During cooling operation, the liquid refrigerant which condenses at the outdoor unit heat exchanger ows into

the receiver tank, and SC (sub-cooling) approaches 32°F (0°C). When SC is small and the length of the tubing

connecting the indoor and outdoor units is long, the refrigerant ow in the indoor unit will be reduced signicantly.

To prevent this trouble from occurring, MOV4 operates so as to increase supercooling in the double tube coil near the outlet of the outdoor unit.

In addition, MOV4 controls refrigerant ow volume so that it will not ow back to the compressor in the liquid state.

SH in suction that is difference between the SCG temperature and low pressure sensor temperature is adjusted to

5.4deg F ~ 9deg F (3deg C ~ 5deg C).

SCG

Gas returns to

accumulator

Control Functions

Liquid

(SC=0deg)

(SH control)

4-10-2. Discharge temperature control of compressor

When the discharge temperature increases to 194°F (90°C) or more, MOV4 opens to 100 pulses to cool down the compressor. MOV4 operates according to the state of the discharge temperature between 20 - 480 pulses. This operation takes priority over SC control.

Liquid

Refrigerant on the inner side evaporates, cooling the liquid refrigerant on the outer side.

Liquid

(Large SC)

MOV4

SCG

Does not fully evaporate, resulting in liquid backup.

Liquid returns to accumulator

Liquid

MOV4

(Discharge temperature control of compressor.)

This operation is continued until discharge temperature decreases to 176°F (80°C) or less.

4-10-3. Discharge temperature and high pressure control in outdoor unit cycle defrost control

When outdoor unit cycle defrost control operates, MOV4 opens to 200 pulses or over.

4-11. Crankcase Heater Control [CH1, CH2]

When the compressor stops, the crankcase heater of its own compressor is turned ON in the following conditions.

● When the discharge temperature ≤ the outdoor air temperature + 27deg F (+15deg C)

● When the outdoor air temperature ≤ 68°F (20°C)

● When the compressor stops and 30 minutes later.

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Page 28

3WAY VRF SYSTEM

5. Outdoor Fan Control

5-1. Fan Mode

These outdoor units utilize a DC fan motor that can be controlled in a maximum of 15 steps (15 modes). However, fan modes 14 and 15 can only be used if high static pressure mode has been set.

* For information concerning EEPROM settings, refer to the eld application functions.

The following table shows the maximum and minimum fan mode and fan forced mode for each unit.

Status of

heat exchanger

Condenser 13 11 12 12

Type of outdoor unit

72 96 120 144

Control Functions

Standard

Evaporator

Maximum value

Condenser 15 15 12 12

High static

pressure mode

setting

Minimum value * 1 1 1 1

Fan forced mode

Silent mode Silent mode 9 9 10 10

* For the sake of protecting temperature of the electrical parts, the minimum values of the fan mode may sometimes increase in accordance with the ambient temperature or the amount of secondary current.

5-1-1. High static pressure mode

The outdoor unit allows a high static pressure changing the settings. The maximum permissible static pressure is 0.01psi (80Pa).

EEPROM setting in each outdoor unit

CODE : 8F

Setting No.

0 Invalid (factory preset mode) 1 High static pressure mode 2 Never use 3 Never use 4 Never use 5 Never use 6 Never use

However, maximum fan mode is upper limit.

Evaporator

Control for fan crack prevention 9 9 7 7

Snowfall sensor control 11 10 8 8

Ambient

temperature

Ambient

temperature

Ambient

temperature

Ambient

temperature

≤

50°F

(10°C)

50°F

(10°C)

50°F

(10°C)

50°F

(10°C)

13 13 12 12

13 13 13 13

15 15 12 12

15 15 13 13

1 - 20

Page 29

3WAY VRF SYSTEM

5. Outdoor Fan Control

5-1-2. Snow removal control (1) Independent control of outdoor unit (control for fan crack prevention)

This control is intended to prevent snow from accumulating on stopped fans. When the outdoor unit is stopped, the fan motor is forcibly started by the control for fan crack prevention’s fan mode.

● Fan motor operates for 45 seconds and stops for 2 hours when ambient temperature is 41.2°F (5.1°C) or

more.

● Fan motor operates for 45 seconds and stops for 1.5 hours when ambient temperature is 32.2°F ~ 41.0°F (0.1°C

~ 5.0°C).

● Fan motor operates for 45 seconds and stops for 1 hour when ambient temperature is 32.0°F (0.0°C) or less.

(2) Control with snow detection sensor (Field supply)

If a snow detection sensor (eld supply) is available, the snowfall-protection hood might be unnecessary

excluding heavy snow region. When set in this mode, the fan motor is forcibly started by the snowfall sensor control’s fan mode. One snow detection sensor can control all outdoor units on the communications wiring. The snow detection sensor must be connected to one of the main units (unit No.1) and it can control all outdoor units in communication wiring.

* To activate this function, it is necessary to set it to all EEPROMs on outdoor PCBs.

CODE: 04

Setting

No.

Snow detection sensor is NOT connected with this unit. But this function is performed according to the signal of the sensor connected with other outdoor unit. (Factory preset mode)

Snow detection sensor is connected with this unit. And this function is performed according to the sensor signal.

Snow detection sensor is NOT connected with this unit. And this function is NOT performed.

Snow detection sensor is connected with this unit. But this function is NOT performed.

Operation

Control Functions

Snow detection

sensor

Setting No.

Fan motor state

in case of snow

System address 1 System address 2 System address 3

Unit No. 1

Unit No. 2

Unit No. 3

* All main outdoor units are connected with same communication wiring.

Unit No. 1

Unit No. 2

Unit No. 3

0 20 20 20 0 1

ON ON

Unit No. 1

Unit No. 2

OFFOFF ON ONON

Unit No. 3

OFF

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Page 30

3WAY VRF SYSTEM

5. Outdoor Fan Control

5-1-3. Silent mode

This unit includes 2 types of silent modes. See the table under the section “5-1. Fan mode” for maximum fan mode in silent mode. Selecting the silent mode results in operation that gives priority to reducing noise, because these modes involve restrictions on outdoor unit fan modes, the capacity will be somewhat reduced. (It may sometimes become a maximum of -5 hp.)

* Maximum fan mode and frequency in silent mode

Type of outdoor unit 72 96 120 144

Fan mode 9 9 10 10

Frequency (Hz) 47.2 59.5 51.1 53.0

* To activate this function, it is necessary to set it to each outdoor unit.

CODE: 05

Setting No. Mode

0 1 2 3 4 5 6 7 8

9 10 11 12

* When the setting is "external input to PCB necessary", this function works by short circuiting "SILENT" pins. * When the setting is "external input to PCB unnecessary", this function always works. * When the setting is "silent priority", max. fan mode is decided in the following formula.

Max. fan mode = 13 - ( 35 – Ambient temperature) / 2 However, minimum fan mode is “6”, maximum is “13”. (When high static pressure mode, max is “15”)

* When the setting is "capacity priority", this function works excluding the following conditions.

Condition that silent mode interrupts Heat exchanger [condenser] of outdoor unit: Ambient temperature ≥ 100.4°F (38°C) Heat exchanger [evaporator] of outdoor unit: Ambient temperature ≤ 35.6°F (2°C) This function will be useful for nighttime in summer.

* When the setting is "controlled in moderation", this function controls both "silent priority" and "capacity priority".

Thereof, “silent priority” fan mode is set within the temperature range of “capacity priority”.

Invalidity (Factory preset mode) - -

Silent priority

Capacity priority

Controlled in moderation

External input to PCB Silent mode

Necessary

Unnecessary

Necessary

Unnecessary

Necessary

Unnecessary

Silent mode

Never use

Silent mode

Never use

Silent mode

Never use

Silent mode

Never use

Silent mode

Never use

Silent mode

Never use

Control Functions

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Page 31

3WAY VRF SYSTEM

5. Outdoor Fan Control

5-2. Fixed Initial Fan Mode

For the rst 30 seconds after operation starts, the mode is xed at the initial mode which was calculated from the

relationship between the ambient temperature and the outdoor unit horsepower.

If the outdoor unit horsepower changes dramatically, the initial mode may be recalculated and may be again xed

for 30 seconds.

5-3. Operation after Fixed Initial Fan Mode

After the xed initial fan mode, the fan mode is increased or decreased according to the operating conditions.

5-3-1. Cooling mode at all indoor units, or else mixed heating/cooling operation when outdoor unit is functioning

as condenser

(1) Fan mode is increased when the pressure sensor temperature is high, and is decreased when the pressure

sensor temperature is low. * The fan mode is always increased when the pressure sensor temperature is 114.8°F (46°C) or higher (in the

case of all cooling mode).

* The fan mode is always increased when the pressure sensor temperature is 123.8°F (51°C) or higher (in the

case of mixed cooling/heating operation).

* The fan mode is always increased when Maximum discharge temperature of inverter compressor in whole

system < High pressure sensor temperature +18deg F (+10deg C).

Control Functions

5-3-2. Heating mode at all indoor units, or else mixed heating/cooling operation when outdoor unit is functioning

as evaporator (1) If the condensation temperature is low, the fan mode is increased at regular intervals. (2) If the condensation temperature is high, the fan mode is decreased in order to prevent excessive loads. (3) The fan mode may be increased when the outdoor liquid temperature drops to 44.6°F (7°C) or below.

1 - 23

Page 32

6. Outdoor Unit CCU (command controller unit) Control

6-1. MOV of Indoor Unit

6-1-1. MOV of each indoor unit operation mode

Mode of indoor unit

Stop

Outdoor unit

(system)

Stop - 20 pulses

Operating - 20 pulses

Thermostat

ON/OFF

3WAY VRF SYSTEM

Control Functions

Fan

Cooling

Heating

* The meaning of outdoor unit “Operating” is functioning as a cooling or heating system at least more than one

compressor operating simultaneously.

*1 SH control adjusts the difference between the liquid temperature and gas temperature in indoor unit.

SH = gas temperature (E3) ~ liquid temperature (E1) Target SH is 1.8deg F ~ 5.4deg F (1deg C ~ 3deg C) when required level of indoor unit is “30” or “31(test run)”.

Note: When the refrigerant amount in the system is adjusted, it is necessary to select test run that the required

level becomes "31".

*2 SC control adjusts the difference between the liquid temperature in indoor unit and condensation temperature in

a system (Tc). SC = Condensation temperature (Tc) - liquid temperature (E1) Target SC is 9deg F ~ 27deg F (5deg C ~ 15deg C) according to operating condition.

Stop - 20 pulses

Operating - 20 pulses

Stop - 20 pulses

Operating ON 60 ~ 480 pulses (SH control *1)

Operating OFF 20 pulses

Stop - 20 pulses

Operating ON 65 ~ 480 pulses (SC control *2)

Operating OFF 55 ~ 80 pulses (Accumulation prevention of refrigerant *3)

Operating OFF *4 20 pulses

*3 MOV pulse changes to 55 for 1 minute when valve pulse continues to be 55 or more 5 minutes.

The purpose is to decrease the ow volume of the refrigerant so that room temperature can be detected with less inuence of heat from the refrigerant.

*4 Only for Concealed Duct - High Static Type Indoor Unit (Type E1)

In case of special controls, MOV performs special operation. For details, see the sections “7. Tube Refrigerant Recovery Control”, “8. Oil Control”, “9. Defrost Control”, “10. Discharge Tube Accumulated Refrigerant Recovery Control”.

1 - 24

Page 33

3WAY VRF SYSTEM

6. Outdoor Unit CCU (command controller unit) Control

6-2. Solenoid Valve Kit Control [SVK]

This device connects the solenoid valve kit which is used to switch between indoor unit cooling/heating for 3WAY types. In case of special controls, solenoid valve kit performs special operation. For details, see the sections “7. Tube Refrigerant Recovery Control”, “8. Oil Control”, “9. Defrost Control”, “10. Discharge Tube Accumulated Refrigerant Recovery Control”.

6-2-1. SVK of each indoor unit operation mode

Mode of indoor unit

Stop

Fan

Cooling

Heating

*1 When the outdoor unit is stopped, all valves of indoor units’ solenoid valve kit in the heating mode are closed.

Next, when the cooling or heating operation is resumed, the valves will be opened.

*2 Function when a common use solenoid valve kit is used and there are more than one (1) indoor unit in the

cooling mode within the same solenoid valve kit.

*3 Function when a common use solenoid valve kit is used and there are more than one (1) indoor unit in the

heating mode within the same solenoid valve kit.

*4 Only for Concealed Duct - High Static Type Indoor Unit (Type E1)

Checker software shows DSBE as the solenoid valve kit status of “0” and “1” instead of “OFF” and “ON” individually.

0 : OFF 1 : ON

Outdoor unit

(system)

Stop - OFF OFF ON/OFF *1 OFF Operating - OFF OFF ON OFF Operating *2 (Cooling) OFF ON ON ON Operating *3 (Heating) ON OFF OFF OFF

Stop - OFF OFF ON OFF Operating - OFF OFF ON OFF Operating *2 (Cooling) OFF ON ON ON Operating *3 (Heating) ON OFF OFF OFF

Stop - OFF OFF ON OFF Operating ON OFF ON ON ON Operating OFF OFF ON ON ON

Stop - OFF OFF ON/OFF *1 OFF Operating ON ON OFF OFF OFF Operating OFF ON OFF OFF OFF Operating OFF *4 OFF OFF OFF OFF

Thermostat

ON/OFF

Discharge

valve

(D)

Suction

valve

(S)

Balance

valve

Control Functions

(B)

valve

(E)

6-3. Indoor Fan Speed Control

CCU intervenes in fan control of the indoor unit according to the state at the operating mode below. The priority order of fan control by CCU is higher than that of indoor unit’s. In case of special controls, indoor fan performs special operation. For details, see the sections “7. Tube Refrigerant Recovery Control”, “8. Oil Control”, “9. Defrost Control”, “10. Discharge Tube Accumulated Refrigerant Recovery Control”.

6-3-1. Stop When the outdoor unit is operating and cooling or heating thermostat ON is changed to OFF, the indoor unit fan stops after 1 minute drive with air speed “L”.

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Page 34

3WAY VRF SYSTEM

6. Outdoor Unit CCU (command controller unit) Control

6-3-2. Dry mode

Indoor unit fan run in the dry mode is controlled from CCU as shown in the below gure.

DTi

Fan speed set by remote controller

Fan speed is “L” when thermostat ON Fan speed is “LL”when thermostat OFF

DTi = (Intake temperature of indoor unit) - (Preset temperature in remote controller)

6-3-3. Heating mode Indoor unit fan run in the heating mode is stopped from CCU at the following conditions.

● Discharge air temperature of indoor unit ≤ 68°F (20°C)

● High pressure sensor temperature (HPS) in outdoor unit ≤ 77°F (25°C)

● Liquid temperature (E1) in indoor unit ≤ 68°F (20°C)

6-4. Drain Pump Control

CCU intervenes in drain pump control of the indoor unit according to the setting in EEPROM in the outdoor unit. The drain pump operates from CCU control at the following conditions.

● DP counter ≥ 5

* The DP counter counts Oil Recovery Control and Tube Refrigerant Recovery Control in cooling operation.

● Liquid temperature (E1) in the indoor unit which selected cooling mode < 32°F (0°C) * Regardless of operating / stopped.

● Concealed Duct - Medium Static tyepe indoor unit Concealed Duct - Medium Static types, dirt might be accumulated when water collects in the drain pan for a long period of time. Therefore, the drain pump works longer to drain water properly. * To activate this function, it is necessary to set it to EEPROM on the main outdoor PCB.

EEPROM setting in main outdoor unit

CODE: 0C

Setting No. Indoor unit under this control

0 Invalid All units 1 DP operates for 20 minutes and stops for 2 hours 2 DP operates for 20 minutes and stops for 20 minutes 3 DP always operates

DP operates for XX minutes when indoor unit's operation

6 Both Setting No. 4 and 5 functions. 7

(Factory

preset mode)

* When setting No. 4 – 7 is selected, this function works only for below indoor unit types. * Types : F2, M2, E1 Operating time mentioned “XX” above is able to set in EEPROM of the main outdoor unit.

changes;

from thermostat ON → thermostat OFF or operation stopped.

DP operates for XX minutes when indoor unit's operation changes;

from thermostat ON or thermostat OFF → operation stopped.

DP operates for XX minutes when indoor unit's operation changes;

from thermostat ON or thermostat OFF → operation stopped.

(Mode, Operation / Stop Thermostat ON / OFF doesn't concern)

Cooling mode Dry mode Heating mode5

Cooling mode Dry mode

Control Functions

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Page 35

6. Outdoor Unit CCU (command controller unit) Control

EEPROM setting in main outdoor unit CODE: 2B

Setting No. XX

20 20 minutes 30 30 minutes (factory preset mode) 40 40 minutes 50 50 minutes 60 60 minutes

* The drain pump always operates when the indoor unit is thermostat ON in cooling operation. * Once the drain pump operates, it keeps operating for 20 minutes. In the above 2 cases, the drain pump operates by the signal of indoor PCB, not by CCU.

3WAY VRF SYSTEM

Control Functions

6-5. Discharge Air Temperature Control

For Type F2, M2, E1 indoor units, discharge air temperature is controlled from the CCU to prevent condensation on duct surface in cooling operation. The CCU monitors and adjusts To of indoor unit. The adjustment is made by compressor capacity and MOV operation in the indoor unit. * To: Cooling (Discharge air temperature) - (Preset discharge air temperature)

Heating (Preset discharge air temperature) - (Discharge air temperature)

Situation in which indoor unit stops by discharge air temperature control

● To ≤ -6.3deg F (-3.5deg C), and this condition continues 7 minutes

● To ≤ -3.6deg F (-2.0deg C), and this condition continues (20 + XX) minutes

*The above mentioned “XX” is able to set in EEPROM of the main outdoor unit.

EEPROM setting in main outdoor unit CODE: E1

Setting No.

-20

-19

-18 -18

0 (factory preset mode)

20 21

Interval of “1”

10 10

* Discharge air temperature in cooling mode is 53.6°F (12°C). * In heating operation, this function virtually does not work because preset discharge air temperature is 122°F

(50°C) and this is sufciently higher than actual discharge temperature.

For preset discharge air temperature that is set in the indoor unit is able to change, refer to manual for indoor unit.

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Page 36

3WAY SYSTEM

Control Functions

7. Tube Refrigerant Recovery Control

3WAY SYSTEM

Control Functions

7. Tube Refrigerant Recovery Control

Control when outdoor unit heat exchanger is acting as an evaporator (when all units are in heating mode or at start of mixed operation when heating load is high)

* When the above operation is finished, normal operation starts at the horsepower determined by the indoor units

where thermostats are ON.

* When the horsepower of heating thermostat ON still remains greater than that of cooling thermostat ON during

control mentioned above, normal control is performed without stopping the compressor.

* When the horsepower of cooling thermostat ON is getting greater than that of heating thermostat ON during

control mentioned above, once stop the outdoor unit after completion of control. Then change the heat exchanger acting as an evaporator to a condenser and resume the operation.

All outdoor units operate at maximum horsepower.

Valves at all indoor units operate at 250 pulses.

Valve kits at all indoor units operate in heating mode (ON status)

Control time

Outdoor units

Expansion valve

Solenoid valve kit

Fan

As for heating thermostat ON indoor units, follow the indoor unit control system.

The fan speed of the heating thermostat OFF Concealed Duct - High Static type indoor unit (Type E1) is changed to LL.

Fan and cooling (thermostat ON/OFF) and/or heating (thermostat OFF) operation of indoor unit will be stopped.

All Indoor Units

Minimum 1 minute – Maximum 20 minutes (Until Tc

95°F (35°C))

3WAY VRF SYSTEM

7. Tube Refrigerant Recovery Control

This control is intended to recover refrigerant if refrigerant has accumulated somewhere in the tubing when the units have been stopped for long periods, as well as to compensate for tubing thermal loss during heating start, and is also used for oil recovery. Special control : Tube Refrigerant Recovery Control features one of the functions of special control.

7-1. Start of Tube Refrigerant Recovery Control

When the microcomputer is initialized immediately after power-ON. After warning output occurs After a set amount of time has elapsed 60 minutes when all outdoor units are stopped.

7-2. Simplified Flow of Tube Refrigerant Recovery Control

Whole Process

Tube refrigerant recovery control shall be performed as the flow mentioned below.

(0) Stopped (1) Tube refrigerant recovery control processing time* (2) Post-processing time of tube refrigerant recovery control for 2 minutes or non stop operation (3) Normal operation

Tube Refrigerant Recovery Control Process

Control function when the outdoor unit heat exchanger is acting as a condenser. (when all units are in cooling mode or at start of mixed operation when the cooling load is high.)

Control time

Outdoor units

2 minutes

All outdoor units operate at maximum horsepower.

Control Functions

Expansion valve

All Indoor Units

* When the above operation is finished, normal operation starts at the horsepower determined by the indoor units

where thermostats are ON.

* When the horsepower of cooling thermostat ON still remains greater than that of heating thermostat ON during

control mentioned above, normal control is performed without stopping the compressor.

* When the horsepower of heating thermostat ON is getting greater than that of cooling thermostat ON during

control mentioned above, once stop the outdoor unit after completion of control. Then change the heat exchanger acting as a condenser to an evaporator and resume the operation.

Solenoid valve kit

Fan

Valves at all indoor units operate at a fixed pulse according to the indoor unit capacity.

Valve kits at all indoor units operate in cooling mode (ON status).

Fan runs at the set fan speed depending on the indoor unit operation mode.

1 - 28

Page 37

3WAY VRF SYSTEM

3WAY SYSTEM

Control Functions

7. Tube Refrigerant Recovery Control

Control when outdoor unit heat exchanger is acting as an evaporator (when all units are in heating mode or at start of mixed operation when heating load is high)

Control time

Minimum 1 minute – Maximum 20 minutes (Until Tc

Control Functions

95°F (35°C))

Outdoor units

Expansion valve

Solenoid valve kit

All Indoor Units

Fan

* When the above operation is finished, normal operation starts at the horsepower determined by the indoor units

where thermostats are ON.

* When the horsepower of heating thermostat ON still remains greater than that of cooling thermostat ON during

control mentioned above, normal control is performed without stopping the compressor.

* When the horsepower of cooling thermostat ON is getting greater than that of heating thermostat ON during

control mentioned above, once stop the outdoor unit after completion of control. Then change the heat exchanger acting as an evaporator to a condenser and resume the operation.

All outdoor units operate at maximum horsepower.

Valves at all indoor units operate at 250 pulses.

Valve kits at all indoor units operate in heating mode (ON status)

As for heating thermostat ON indoor units, follow the indoor unit control system.

Fan and cooling (thermostat ON/OFF) and/or heating (thermostat OFF) operation of indoor unit will be stopped.

The fan speed of the heating thermostat OFF Concealed Duct - High Static type indoor unit (Type E1) is changed to LL.

1 - 29

Page 38

8. Oil Control

3WAY SYSTEM

Control Functions

8. Oil Control

3WAY VRF SYSTEM

Control Functions

8-1. Oil Level

Oil level JudgementConditions of oilMeaning

2 Sufficient The compressor contains sufficient oil. There is no problem.

Confirm that oil is returned after

1 Slightly low There will be a risk of oil shortage soon.

0 Extremely low

At the time immediately after the oil level changes from 2 to 1, there is a specified amount of oil in the compressor. Namely, soon after the oil level is changed to 1, the oil in the compressor is sufficient. If the oil level “0” indication continues for more than 5 to 10 minutes, it seems short of oil in the system. Check valves related to oil recovery operation, the refrigerant tubing and for any oil leakage.

8-2. Oil Level Detection

The compressor oil in the crankcase is sent by bypass via a capillary tube to the low-pressure circuit. The temperature detected by an oil sensor is used to determine whether it is oil (warm) or refrigerant (cold).

The compressor oil is short against required level for normal operation.

performing the oil recovery control operation.

Confirm that oil level is recovered to the required level after performing the oil recovery control between systems.

8-3. Self-Separator Oil Recovery Control

When a low oil level (1 or 0) is detected, oil is recovered from the oil separator to the compressor though ORVR.

8-4. Inter Outdoor Units Oil Recovery Control – Utilizing Balance Tubes

If the low oil level (1 or 0) continues, that outdoor unit (oil-receiving outdoor unit) receives oil from operating outdoor units where the oil level is not low (oil-supply outdoor units whose all compressor oil levels are 2).

Control at the oil-receiving outdoor unit begins 30 seconds after an outdoor unit falls into oil level 0.

Control at the oil-receiving outdoor unit begins 120 seconds after an outdoor unit falls into oil level 1.

Oil supply is performed for a maximum of 5 minutes from each unit.

When oil supply is ended, oil supply from that outdoor unit will not occur again for a period of [(No. of outdoor units minus 1) × 5 minutes]. In addition, oil supply is ended if the oil-receiving outdoor unit oil level changes to 2, or if the oil-supply outdoor unit oil level becomes "0".

The supply of oil is received from 1 unit at a time, in sequence, according to the order of priority of their inverter compressors.

Operation during unit refrigerant oil recovery

[A] Oil-receiving outdoor unit

ORVR turns ON and remains ON.

[B] Oil-supply outdoor unit

BPV turns ON and remains ON.

BPV bypass valve repeatedly turns ON and OFF according to a constant cycle.

* This oil recovery might be performed regardless of oil level according to operating condition.

1 - 30

Page 39

3WAY VRF SYSTEM

3WAY SYSTEM

Control Functions

8. Oil Control

8-5. System Oil Recovery Control

Control Functions

Special control : System Oil Recovery Control features one of the functions of special control.

8-5-1. Start of system oil recovery control

When operating compressor oil level 0

When operating inverter compressor oil level less than 1 is counted with accumulation for up to 60 minutes.

8-5-2. Simplified flow of system oil recovery control

Whole process

System oil recovery control shall be performed as the flow mentioned below.

(0) Normal operation (1) Pre-processing time of system oil recovery control for 2.5 minutes (2) System oil recovery control processing time* (3) Post-processing time of system oil recovery control for 2 minutes (4) Normal operation

System oil recovery control process

Surely perform this system control by cooling cycle. Even if the outdoor unit heat exchanger is functioning as an evaporator (all heating mode or mixed cooling/ heating operation), change the outdoor unit, indoor unit and solenoid valve kit to the cooling cycle and perform the system oil recovery control.

* If just before the operation is in heating mode or cooling/heating mixed operation mode, system oil recovery control may sometimes be performed by only 1st heat exchanger or all heat exchanger.

Outdoor units

All Indoor Units

Control time

Expansion valve

Solenoid valve kit

Fan

3 minutes

All outdoor units operate at maximum horsepower.

Valves at all indoor units operate at a fixed pulse according to the indoor unit capacity.

Valve kits at all indoor units operate in cooling mode (ON status).

Stop and cooling (thermostat ON/OFF) and/or heating (thermostat ON) operation of indoor units will be followed the indoor unit control system.

Fan and/or heating (thermostat OFF) operation of indoor unit will be stopped.

The fan speed of the heating thermostat OFF Concealed Duct - High Static type indoor unit (Type E1) is changed to LL.

1 - 31

Page 40

8. Oil Control

3WAY SYSTEM

Control Functions

8. Oil Control

3WAY VRF SYSTEM

Control Functions

8-6. Oil Rotation Control

The oil rotation control system regularly exchanges oil among the outdoor units regardless of oil level.

Oil rotation control is performed every one hour with accumulated operation time among the connected multiple outdoor units only.

During oil rotation control, ORVR may open in the order of priority of outdoor unit inverter compressor operation every 5 minutes.

8-7. Indoor Unit Self Oil Recovery Control

The indoor unit self oil recovery control system can only be performed by the cooling indoor units.

Divided into 8 groups in the order of indoor unit addresses and this oil recovery control is performed every

190 minutes with accumulated operation time per each group for 1 minute.

The indoor unit expansion valve is opened according to the values determined by the indoor unit capacity with thermostat OFF.

10 pulses is opened from the pulse controlling the indoor unit expansion valve with thermostat ON. Then, the fan speed is changed to L.

1 - 32

Page 41

9. Defrost Control

3WAY SYSTEM

Control Functions

9. Defrost Control

9-1. Defrost Methods

This system uses the following 2 defrosting systems.

3WAY VRF SYSTEM

Control Functions

System employs

1 outdoor unit in the refrigerant system

2 or more outdoor units in the refrigerant system

9-2. Constraint Conditions

Frost detection does not occur for 10 minutes after operation starts.

Defrost does not begin again for 40 minutes of operation after defrost was once completed.

If all indoor units are stopped while defrosting, or if the outdoor unit is stopped due to protection control or another reason, then defrost control will not start for a minimum of 5 minutes after restart occurs.

Time until next defrost permission when defrost was completed is changed according to the ambient temperature.

Ambient temperature

Minute XX + 6 XX + 3 XX

EEPROM setting in main outdoor unit CODE: A3

Setting No.

20 21

To ≤ 14°F (-10°C) 14°F (-10°C) < To ≤ 23°F (-5°C)

XX 20 21

Defrost control method

Reverse cycle defrost

Outdoor unit cycle defrost

23°F (-5°C) < To

40 41

Interval of “1”

40 (factory preset mode)

Never use

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Page 42

9. Defrost Control

3WAY SYSTEM

Control Functions

9. Defrost Control

3WAY VRF SYSTEM

Control Functions

9-3. Frost Detection

(1)

Frost detection does not occur for 5 minutes after operation starts.

(2) Frost is detected when either condition 1 or 2 below is met.

Condition 1: L2 line or below is detected twice, each time continuously for 4 minutes, when the compressor

is operating.

Condition 2: L1 line or below is detected for a total of 60 minutes when the compressor is operating.

Heat exchange liquid temperature °F (°C)

-13 (–25)

59 (15)

30.2 (–1)

26.6 (–3)

17.6 (–8)

Defrosting operation end temperature

50 (10) External temperature °F (°C)

14 (–10)

The frost detection area is located under the thick lines

(The end temperature is different from the above detection temperature.)

-13.9 (–25.5)

-17.5 (–27.5)

9-4. Reverse Cycle Defrost

Reverse cycle defrost is performed in systems where only 1 outdoor unit is connected to the refrigerant system.

Special control : Reverse Cycle Defrost features one of the functions of special control.

9-4-1. Start of reverse cycle defrost

When conditions of section “9-2” and “9-3” contents are satisfied, defrost control is started.

9-4-2. Simplified flow of reverse cycle defrost

Whole process

Reverse cycle defrost shall be performed as the flow mentioned below.

(0) Normal operation (1) Pre-processing time of reverse cycle defrost for 2.5 minutes (2) Reverse cycle defrost processing time* (3) Post-processing time of reverse cycle defrost for 2 minutes (4) Normal operation

1 - 34

Page 43

3WAY VRF SYSTEM

3WAY SYSTEM

Control Functions

9. Defrost Control

Reverse cycle defrost process*

This reverse cycle defrost process is performed after outdoor units, indoor units and solenoid valve kits are changed to the cooling cycle.

Control Functions

All Indoor Units

Evaporator

Control time

Outdoor units

Expansion valve

Solenoid valve kit

Fan

Stop Stop

Defrost (DEF)

Stop

Minimum 1 minute – Maximum 15 minutes (Until all outdoor units’ heat exchanger temperature ≥ 59°F (15°C))

Outdoor unit operates at maximum horsepower.

Valves at all indoor units operate at a fixed pulse according to the indoor unit capacity.

Valve kits at all indoor units operate in cooling mode (ON status).

Stop and cooling operation of indoor units will be followed by the indoor unit control system.

Fan and heating operation of indoor units are changed to stop.

DefrostStopHeating HeatingStop

Defrost (DEF)

Stop

Defrost (DEF)

Evaporator

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Page 44

9. Defrost Control

3WAY SYSTEM

Control Functions

9. Defrost Control

3WAY VRF SYSTEM

Control Functions

9-5. Outdoor Unit Cycle Defrost

Outdoor unit cycle defrost is performed in systems where 2 or more outdoor units are connected to the refrigerant system. With this defrost method, when 1 outdoor unit operates in defrost mode (heat exchanger operating as a condenser), another outdoor unit operates as an evaporator in the same way as in ordinary heating mode. In this way, the other outdoor unit is heating the unit where defrost is occurring. When 1 outdoor unit completes defrost, the other outdoor unit performs defrost in the same way. Because the amount of time that the unit operates as an evaporator is very short, there is little danger of frost forming again quickly. Rather, because the heat source is very powerful, it is possible to shorten defrost operating time.

9-5-1. Start of outdoor unit cycle defrost

When 1 or more connected outdoor units are satisfied with the conditions of section “9-2” and “9-3” contents, defrost control is started.

Outdoor unit cycle defrost is performed in all connected outdoor units.

9-5-2. Simplified flow of outdoor unit cycle defrost

Whole process

Outdoor unit cycle defrost shall be performed as the flow mentioned below.

(0) Normal operation (1) Outdoor unit cycle defrost processing time (2) Normal operation

Outdoor unit cycle defrost process

Outdoor unit cycle defrost is always completed in 2 defrost operations. (1) When there are 2 outdoor units

Defrost outdoor unit

First operation Second operation

(2) When there are 3 outdoor units

Defrost outdoor unit

Evaporator outdoor unit

Switch to

Evaporator outdoor unit

Defrost outdoor unit

Second operationFirst operation

Defrost outdoor unit

1 - 36

Page 45

9. Defrost Control

E : Evaporator operation C : Condenser operation S : Stop or shut off the refrigerant

E→C : Switching from evaporator operation to condenser operation C→E : Switching from condenser operation to evaporator operation

Outdoor unit cycle defrost processing

Normal

operation

Outdoor

unit

delay-start

control

Defrost

group

1st

Switch

2nd

Defrost

group

3WAY VRF SYSTEM

Control Functions

Normal

Switch

operation

Outdoor

unit(s)

Control time - 1 min

Heat

Defrost

occurs

rst

Defrost

occurs

second

Mode Thermostat

Stop

exchanger

Compressor ON ON ON OFF ON OFF ON

Fan ON OFF OFF OFF ON OFF ON

Heat

exchanger

Compressor ON or S ON ON OFF ON OFF ON or S

Fan ON or S ON ON OFF OFF OFF ON or S

- S S S S S S S

*1(Cooling) S S S S S S S

*2(Heating) S S S S S S S

- S S S S S S S

E or S E E

E→C C C S S

S S C C C→E

Max 10 min

1 min

E→C C C S

S S C C

Max 10 min

E E E

1 min -

C→E E or S

Indoor

units

*1 Function when a common use solenoid valve kit is used and there are more than one (1) indoor unit in the

cooling mode within the same solenoid valve kit.

*2 Function when a common use solenoid valve kit is used and there are more than one (1) indoor unit in the

heating mode within the same solenoid valve kit.

*3 Only for Concealed Duct - High Static Type Indoor Unit (Type E1)

Fan

Cooling

Heating

*1(Cooling) S S S S S S S

*2(Heating) S S S S S S S

ON E E E E E E E

OFF S S S S S S S

ON C S S S S S C

OFF C S S S S S C

OFF *3 S S S S S S S

1 - 37

Page 46

3WAY VRF SYSTEM

9. Defrost Control

● Indoor unit (expansion valve, solenoid valve kit, fan)

Outdoor unit cycle defrost processing

Normal

operation

Mode Thermostat

Stop

Heating

Fan

Cooling

Stop

Fan

Cooling

Stop

Fan

Cooling

Expansion

valve

Unit : pulse

Solenoid

valve

kit

Fan

*1 Function when a common use solenoid valve kit is used and there are more than one (1) indoor unit in the

cooling mode within the same solenoid valve kit.

*2 Function when a common use solenoid valve kit is used and there are more than one (1) indoor unit in the

heating mode within the same solenoid valve kit. *3 Only for Concealed Duct - High Static Type Indoor Unit (Type E1) *4 Fan runs at the set fan speed depending on the indoor unit operation mode. *5 Individual number for DSBE indicates the status (OFF/ON) in turn from left respectively.

0 : OFF

1 : ON

*1(Cooling) *2(Heating)

ON SH control SH control SH control SH control SH control SH control SH control

OFF

*3 OFF

*1(Cooling) *2(Heating)

OFF

*3 OFF

*1(Cooling) *2(Heating)

OFF

*3 OFF

20 20 20 20 20 20 20

55 55 60 60

20 20 20 20 20 20 20

20 20 20 20 20

55 55 60

20 20 20 20 20 20 20

SC control SC control 60 60 60 60 SC control

55 55 60 60 60 60 55

20 20 20 20 20 20 20

0010 0010 0010 0010 0010 0010 0010

0111 0111 0 111 0111 0111 0111 0111

1000 0000 0000 0000 0000 0000 0000

0010 0010 0010 0010 0010 0010 0010

0111 0111 0 111 0111 0111 0111 0111

1000 0000 0000 0000 0000 0000 0000

0111 0111 0 111 0111 0111 0111 0111

1000 0000 0000 0000 0000 0000 1000

0000 0000 0000 0000 0000 0000 0000

*4 *4 *4 *4 *4 *4 *4

*4 *4

*4 *4 *4 *4 *4 *4 *4

*4 *4

Indoor unit delay-start

control

1st

Defrost

group

Stop Stop Stop Stop

LL LL LL LL

Switch

60 60 60

2nd

Defrost

group

Control Functions

Normal

Switch

60 55

operation

1 - 38

Page 47

10. Discharge Tube Accumulated Refrigerant Recovery Control

10-1. Start of Discharge Tube Accumulated Refrigerant Recovery Control

When any of them is completed, this control is implemented. (1) More than 90 minutes, more than one indoor unit for judgment of discharge tube accumulated refrigerant (2) More than 60 minutes, indoor unit for judgment of discharge tube accumulated refrigerant :

Indoor unit total amount ≥ 1/3 thermostat ON HP

(3) More than 30 minutes, indoor unit for judgment of discharge tube accumulated refrigerant :

Indoor unit total amount ≥ 1/3 thermostat ON HP

Judgment of discharge tube accumulated refrigerant

● Indoor unit operating mode with cooling thermostat ON

● Indoor unit electronic control valve opened more than 300 pulses

● Difference between suction temperature and discharge temperature is less than 5.4deg F (3deg C).

3WAY VRF SYSTEM

Control Functions

10-2. Simplied Flow of Discharge Tube Accumulated Refrigerant Recovery Control

● Whole process

Discharge tube accumulated refrigerant recovery control shall be performed as the ow mentioned below.

(0) Normal operation (1) Time before discharge tube accumulated refrigerant recovery control 3.0 minute stop (2) Discharge tube accumulated refrigerant recovery control processing time * (3) Time after discharge tube accumulated refrigerant recovery control 4 minute stop (4) Normal operation

*1 Discharge tube accumulated refrigerant recovery control process

This discharge tube accumulated refrigerant recovery control process is performed after outdoor units, indoor units and solenoid valve kits are changed to the heating mode.

Minimum 1 minute – Maximum 5 minutes (Until all outdoor unit’s HPT ≥ 68°F (20°C))

· As for stop and heating indoor units, follow the indoor unit control system.

· Fan and cooling indoor unit will be stopped.

All

Indoor

Units

Control time

Outdoor unit Outdoor unit operates at maximum horsepower.

Expansion valve Valves at all indoor units operate at 250 pulses.

Solenoid Valve Kit Valve kits at all indoor units operate in heating mode (ON status).

Fan

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Page 48

11. Upper Current Limitation Mode (Demand control)

3WAY SYSTEM

Control Functions

10. Upper Current Limitation Mode (Demand control)

There are 2 types of control; demand control and infinity limit in the upper current limitation mode. Either of them is controlled by the lower current limitation.

The standard value of the limit current is listed in the table below.

U-72MF2U9 / U-96MF2U9 / U-120MF2U9 / U-144MF2U9

Type of outdoor unit

Cooling mode

72 96 120 144

14.4 A 23.0 A 26.8 A 36.8 A

3WAY VRF SYSTEM

Control Functions

Heating mode

Mixed mode (Cooling/Heating) 16.4 A 25.0 A 28.8 A 38.3 A

U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94

Type of outdoor unit

Cooling mode

Heating mode

Mixed mode (Cooling/Heating) 7.8 A 11.0 A 13.6 A 17.9 A

11-1. Demand Control

Serial-parallel I/O must be connected in order to perform demand control. The below input is received by serial-parallel I/O, and demand control is performed.

The demand values can be set as needed with serial-parallel I/O.

Upper current limitation setting

Contact 1

Contact 2

16.4 A 25.0 A 28.8 A 38.3 A

72 96 120 144

6.7 A 10.0 A 12.8 A 17.2 A

7.8 A 11.0 A 13.6 A 17.9 A

Control

No control (Operates to maximum capacity)

Operates to XX% of the upper limit for the rated current.

Operates to YY% of the upper limit for the rated current.

Forced thermostat OFF setting

: Input present

: Input not present

* The rated current indicates the current value that is listed in the catalog or similar material.

* XX and YY are able to set in EEPROM of main outdoor unit.

EEPROM setting in main outdoor unit

CODE: 1A

Setting No. XX

0 0 40 40 45 45

Interval of “5”

100 100 (factory preset mode)

140 140

-1 No control

CODE: 1B

Setting No. YY

0 0 40 40 45 45

Interval of “5”

70 70 (factory preset mode)

140 140

-1 No control

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Page 49

11. Upper Current Limitation Mode (Demand control)

3WAY SYSTEM

Control Functions

10. Upper Current Limitation Mode (Demand control)

It is able to display the present condition on the remote controller.

EEPROM setting in main outdoor unit

CODE: 1E

Setting No.

0 No display

1 When demand control active, “demand - actived” displayed (factory preset mode).

2 When forced thermostat OFF with demand control active, “demand - actived” displayed.

11-2. Upper Current Limitation Mode

Even if the demand control is not performed, upper current limitation is restricted.

U-72MF2U9 / U-96MF2U9 / U-120MF2U9 / U-144MF2U9

Type of outdoor Unit

72 96 120 144

3WAY VRF SYSTEM

Control Functions

Limited ratio against standard value

Cooling mode

Limit value

Mixed mode (Cooling/Heating)

U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94

Type of outdoor Unit

Limited ratio against standard value

Limit value

Mixed mode (Cooling/Heating)

11-3. When Using Demand Terminal Block* *Demand Terminal Block is the field supply parts.

Demand terminal block must be connected in order to perform the demand control. (It is also possible to connect the optional Seri-Para I/O unit (optional CZ-CAPDC2) and setup the system.) The current limitation values can be set by changing either contact.

COM short circuit

Non

DRM3

DRM2

DRM1

Heating mode

Cooling mode

Heating mode

Seri-Para I/O unitDemand terminal block

Contact 1 Contact 2

140% 140% 140% 140%

18.2 A 30.2 A 35.5 A 45.0 A

21.0 A 33.0 A 38.3 A 45.0 A

72 96 120 144

140% 140% 140% 140%

8.4 A 13.0 A 16.9 A 23.1 A

9.9 A 14.4 A 18.0 A 24.1 A

Control

No control (Operates to maximum capacity.)

Operates to 100% of the upper limit for the rated current

Operates to 70% of the upper limit for the rated current

Forced thermostat OFF setting

: Input present : Input not present

* The rated current indicates the current value that is listed in the catalog or service manual.

**In respect of connection method for demand terminal block and Seri-Para I/O unit, refer to the installation

instructions supplied with the unit.

During setting in DRM1 - DRM3, [CZ-RTC5A] (demand-activated) displays on the

remote controller of the indoor unit.

[CZ-RTC4]

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Page 50

12. Backup Operation

3WAY SYSTEM

Control Functions

12. Backup Operation

3WAY VRF SYSTEM

Control Functions

12-1. Automatic Backup Operation

This system includes a function for automatic backup operation. An alarm is displayed on the remote controller to inform the user that a failure has occurred.

12-1-1. Alarms that result in automatic backup operation

When the following alarm occurs, automatic backup operation is engaged. Automatic backup operation is not engaged in cases of serious alarm such as communications alarms, etc.

Alarm list 1 (Backup operation continues unless power supply of all outdoor units is turned off.)

Alarm display

H01

H11

H03

H13

H07

Overcurrent in 1st compressor

Overcurrent in 2nd compressor

Current sensor for the 1st compressor is disconnected or shorted

Current sensor for the 2nd compressor is disconnected or shorted

HIC for 1st compressor has failure Overcurrent or overheat of HIC

HIC for 2nd compressor has failure Overcurrent or overheat of HIC

Low on oil or the oil recovery circuit has restriction

AH31

AH21

P16

P26

P29

A :

When there is one outdoor unit in the system, only compressor that has sensor failure stops. When there are multiple outdoor units in the system, only the outdoor unit which contains the problem stops but the other outdoor units in the system operate normally.

B :

When there is one outdoor unit in the system, the backup operation does not work. When there are multiple outdoor units in the system, only the outdoor unit which contains the problem stops but the other outdoor units in the system operate normally.

NOTE :

After automatic backup operation caused by alarm listed in alarm list 1, it will not be canceled automatically when the repair of the failed outdoor unit is completed. Automatic backup mode will be canceled only when the power on all outdoor unit is reset. Therefore, after repair work is completed, be sure to check whether or not automatic backup mode has been canceled.

Overcurrent of 1st compressor on the secondary side of inverter circuit, or inverter failed to syncronize with rotation

Overcurrent of 2nd compressor on the secondary side of inverter circuit, or inverter failed to syncronize with rotation

Inverter for 1st compressor failed to start or failed to syncronize with rotation

Inverter for 2nd compressor failed to start or failed to syncronize with rotation

Fan motor or inverter drive of outdoor unit has failure BP22

AP19

1 - 42

Page 51

12. Backup Operation

3WAY SYSTEM

Control Functions

12. Backup Operation

Alarm list 2 (Backup operation continues as long as the problems are not solved.)

Alarm display

3WAY VRF SYSTEM

Control Functions

F04

F05

F06

F07

F08

F12

F14

F16

F17

F23

F24

H05

H08

H15

H27

P03

DISCH1 thermistor at the discharge of 1st compressor reading is abnormal

DISCH2 thermistor at the discharge of 2nd compressor reading is abnormal

EXG1 thermistor at the gas side of 1st heat exchanger of the outdoor unit has failure (EXG1)

EXL1 thermistor at the liquid side of 1st heat exchanger of the outdoor unit has failure (EXL1)

TO thermistor for outdoor ambient air temperature has failure (TO)

SCG thermistor at the outlet of subcooling heat exchanger in outdoor unit has failure (SCG)

High pressure sensor of the outdoor unit has failure (HPS)

Low pressure sensor of the outdoor unit has failure (LPS)

EXG2 thermistor at the gas side of 2nd heat exchanger of the outdoor unit has failure (EXG2)

EXL2 thermistor at the liquid side of 2nd heat exchanger of the outdoor unit has failure (EXL2)

DISCH1 thermistor at the discharge of 1st compressor is disconnected, shorted or misplaced (DISCH1)

OIL1 thermistor for the oil of 1st compressor has failure (OIL1)

DISCH2 thermistor at the discharge of 2nd compressor is disconnected, shorted or misplaced (DISCH2)

OIL2 thermistor for the oil of 2nd compressor has failure (OIL2)

1st compressor discharge temperature too high

BSCT thermistor at the suction refrigerant of compressors has failure (SCT)

P17

When there is one outdoor unit in the system, only compressor that has sensor failure stops.

A :

When there are multiple outdoor units in the system, only the outdoor unit which contains the problem stops but the other outdoor units in the system operate normally.

B :

* Backup operation caused by an alarm listed in “alarm list 2” will finish automatically after 24 hours if the same

alarm does not occur again for 24 hours.

12-1-2. Start of automatic backup operation

If the above alarms occur, the alarm is displayed on the remote controller, etc. Pressing the remote controller button again starts automatic backup mode.

12-1-3. Backup operation information display

If a wired remote controller is present,

2nd compressor discharge temperature too high

display blinks during operation.

1 - 43

Page 52

3WAY VRF SYSTEM

2WAY VRF SYSTEM

Control Functions

11. Backup Operation

2WAY VRF SYSTEM

Control Functions

11. Backup Operation

All compressors of outdoor unit number 2 are backed up

Unit No. 1

Main unit

CCU function

Unit No. 2

Sub unit

Unit No. 3

Sub unit

Unit No. 1

Main unit

CCU function

Unit No. 2

Sub unit

Unit No. 3

Sub unit

Main outdoor unit Sub outdoor unit Sub outdoor unit Number of setting 2 Not necessary Not necessary Unit No. 123

All compressors in unit No. 2 are backed up. Therefore the setting No. of outdoor units installed on the main outdoor PCB is changed to “2” from “3”.

All compressors of main outdoor unit are backed up

All compressors in unit No. 1 are backed up. Therefore the setting No. of outdoor units installed on the main outdoor PCB is changed to “2” from “3”.

Same setting

Examples:

Combination of 3 outdoor units with 2 compressors

Examples:

Combination of 3 outdoor units with 2 compressors

12-2-2. Disabling operation of one compressor (Type: 120, 144)

At the SW7 switch on the PCB of the failed outdoor unit, turn ON the switch for the compressor to disable, and turn ON the “BACKUP” switch (SW7).

SW7 switches to turn ON

Type of outdoor unit

In the case of

1st compressor

U-120MF2U9 U-144MF2U9

OFF

BACKUPINV

INV2 / AC

In the case of

2nd compressor

OFF

BACKUPINV

INV2 / AC

U-120MF2U94 U-144MF2U94

OFF

BACKUPINV1

INV2

OFF

BACKUPINV1

INV2

12. Backup Operation

Control Functions

12-1-4. Check for blinks when automatic backup setting

When operating the automatic backup by setting the outdoor unit EEPROM, blink check on the remote controller and centralized control systems is enabled to change for non-displayed.

EEPROM setting in main outdoor unit CODE: 49

Setting No.

0 1

12-2. Manual Backup Operation

The manual backup can be used when it is necessary to close the service valve for maintenance, etc.

Backup operation procedure

12-2-1. Disconnecting the failed outdoor unit

(1) Reduce the number of outdoor units set at outdoor unit No.1 by only the number of failed outdoor units. (2) At the SW7 switch on the PCB of the failed outdoor unit, turn ON the switches for all compressor to disable,

and turn ON the “BACKUP” switch (SW7).

Type of outdoor unit

SW7 switches to turn ON

Type of outdoor unit

SW7 switches to turn ON

Display (factory present mode)

Non-displayed

U-72MF2U9 U-96MF2U9

INV1 + BACKUP

INV

INV1 + BACKUP

AC2

AC1

BACKUP

U-72MF2U94 U-96MF2U94

INV1 BACKUP

INV2

INV1 + INV2 + BACKUP

OFF

INV1 + INV2 + BACKUP

OFF

U-120MF2U9 U-144MF2U9

OFF

BACKUPINV

INV2 / AC

U-120MF2U94 U-144MF2U94

OFF

BACKUPINV1

INV2

(3) Close all service valves at the failed outdoor units. (4) Reset the power at outdoor unit No. 1.

* The outdoor unit that backed up all compressors is not controlled by CCU (main outdoor unit).

Even if all compressors of the main outdoor unit are backed up, they are not controlled by CCU. However, the CCU function stays active.

1 - 44

Page 53

3WAY VRF SYSTEM

2WAY VRF SYSTEM

Control Functions

11. Backup Operation

12. Backup Operation

12-2-2. Disabling operation of one compressor (Type: 120, 144)

At the SW7 switch on the PCB of the failed outdoor unit, turn ON the switch for the compressor to disable, and turn ON the “BACKUP” switch (SW7).

Control Functions

Type of outdoor unit

In the case of

1st compressor

SW7 switches to turn ON

In the case of

2nd compressor

All compressors of outdoor unit number 2 are backed up

Examples:

Combination of 3 outdoor units with 2 compressors

Unit No. 1

Main unit

CCU function

Main outdoor unit Sub outdoor unit Sub outdoor unit Number of setting 2 Not necessary Not necessary Unit No. 123

All compressors in unit No. 2 are backed up. Therefore the setting No. of outdoor units installed on the main outdoor PCB is changed to “2” from “3”.

Unit No. 2

Sub unit

Same setting

U-120MF2U9 U-144MF2U9

OFF

BACKUPINV

INV2 / AC

OFF

BACKUPINV

INV2 / AC

Unit No. 3

Sub unit

U-120MF2U94 U-144MF2U94

OFF

BACKUPINV1

INV2

OFF

BACKUPINV1

INV2

All compressors of main outdoor unit are backed up

Examples:

Combination of 3 outdoor units with 2 compressors

Unit No. 1

Main unit

CCU function

Main outdoor unit Sub outdoor unit Sub outdoor unit Number of setting 2 Not necessary Not necessary Unit No. 123

All compressors in unit No. 1 are backed up. Therefore the setting No. of outdoor units installed on the main outdoor PCB is changed to “2” from “3”.

Unit No. 2

Sub unit

Unit No. 3

Sub unit

1 - 45

Page 54

13. Other Functions

3WAY SYSTEM

Control Functions

13. Other Functions

13-1. Maintenance Function for Power Supply Stop of Indoor Unit (E06 ignore)

The system can continue operation even if outdoor unit cannot communicate with some indoor units. It is necessary to set to EEPROM the allowed number of operating indoor units not to be able to communicate. The system will continue operating until the following condition is made to be satisfied.

Value set by the code “23” ≥ No. of indoor units operated until the last moment because of communicative

disorder caused by power supply stop (excluding stopped indoor units). However, the upper limit value set by the code "23" must be less than 25% of the total number of indoor units of the system.

EEPROM setting in main outdoor unit CODE: 23

-1

0 0

1 1

2 2

3WAY VRF SYSTEM

Control Functions

Allowed number of missing indoor unitSetting No.

This function is invalid

(factory preset mode)

Interval of “1”

13 13

Never use

* However, the upper limit value set by the code "23" must be less than 25% of the total number of indoor units of the system.

Examples :

In case of 8 indoor units, setting No. becomes “2”.

Normal operation

Operation continue: Indoor unit failure=2 ≤ Setting No. “2”

ON ON ON ON ON OFF OFF OFF

Error occurs: Indoor unit failure=3 > Setting No. “2”

ON ON ON ON ON OFF OFF OFF

Operation continue: Stopped units does not count

ON ON ON ON ON OFF OFF OFF

1 - 46

Page 55

3WAY VRF SYSTEM

13. Other Functions

13-2. Setting when at Thermostat OFF

13-2-1. Thermostat OFF in cooling mode

When decreasing the indoor airow volume at the cooling thermostat OFF or dry thermostat OFF, follow the setting

procedure below.

EEPROM setting in main outdoor unit CODE: ED

Setting No. Indoor fan mode

0 (factory preset mode) w/o force w/o force w/o force w/o force

1 STOP *3 20 0010 w/o force 2 LL 20 0010 w/o force 3 Interval mode *4 20 0010 w/o force 4 Never use - - -

*1 If setting at thermostat ON, the system will return to the normal indoor fan control or solenoid valve kit mode. *2 Whenever changing thermostat ON and OFF, solenoid valve kit sounds ON and OFF. *3 When setting at Stop mode, be sure to set the room sensor to the remote control thermostat.

Indoor unit

expansion valve

SVK Louver

Control Functions

EEPROM setting in indoor unit CODE: 32

Setting No.

0 Indoor unit sensor (factory preset mode) 1 Remote control sensor

*4 Operation when in the intermittent airow setting

• When in the thermostat OFF, LL airow and stop mode repeats alternately and the mechanical valve and

solenoid valve kit remain in the forced condition.

• Interval intermittent operation can be changed by EEPROM setting.

EEPROM setting in indoor unit CODE: 44

Setting No.

30 30

60 (factory preset mode) 60

90 90

210 210 240 240

Indoor unit fan operating

time [sec]

CODE: 45

Setting No.

5 (factory preset mode)

10 10

15 20 25 30

Indoor unit fan stopped

time [min]

15 20 25 30

13-2-2. Thermostat OFF in heating mode If setting without hot air in heating thermostat OFF, follow the setting procedure below.

EEPROM setting in main outdoor unit CODE: CD

Setting No.

0 (factory preset mode) w/o force w/o force

1 20 0000

*1 If setting at thermostat ON, the system will return to the normal indoor fan control or solenoid valve kit mode. *2 Whenever changing thermostat ON and OFF, solenoid valve kit sounds ON and OFF.

Indoor unit

expansion valve

SVK

1 - 47

Page 56

3WAY VRF SYSTEM

14. Detailed Settings in EEPROM of Outdoor Unit

Never use the DN code unlisted in the following table. (P) : Factory preset mode

DN Item Setting No.

0=No sensor & control (P)

04 Operation for using snowfall sensor

05 Outdoor fan silent mode

0C Indoor unit drain pump forced operation

Measures against smell when indoor

unit cooling thermostat OFF

1A Demand 1 current (%)

1B Demand 2 current (%)

1E Demand remote controller display

23 E06 ignore function

Dew condensation prevention control of

indoor unit

2B DP operation time for slime measures

3E PSccutgt delay-start setting

Indoor unit fan's intermittent operation

and operating time when in cooling thermostat OFF Indoor unit fan's intermittent operation

and stopped time when in cooling thermostat OFF

49 Automatic backup mode setting 0=Display (P) 1=non-displayed

81 Outdoor unit capacity

8F High static pressure setting

The minimum operating time 1 until

defrosting Validity/invalidity of capacity control

when cooling operation

1=Sensor & control 2=No Sensor & no control 3=Sensor & no control 0=Invalid (P) 1=Silent mode 1 2=Silent mode 2 ,,,,, 12=Silent mode 12 0=Invalid 1=stop for 2 hours and drive for 20 min. constantly 2=stop for 20 min. and drive for 20 min. constantly 3=Drive constantly 4-6=delay drive when thermostat OFF 7=delay drive when thermostat OFF (P) 0=Invalid (P) 1=Measures against smell 0=0% ,,,,,40=40% ,,,,,45=45% ,,,,,100=100% (P) ,,,,,140=140%

-1=No control 0=0% ,,,,,40=40% ,,,,,70=70% (P) ,,,,,100=100% ,,,,,140=140%

-1=No control 0=No display 1=When demand control active, “demand - actived” displayed (P) 2=When forced thermostat OFF with demand control active, “demand - actived” displayed

-1=invalid (P),,,,, 0=0,,,,, 1=1,,,,, 13=13 14-52=Never use 0=Invalid (P) 1=30 min, 2=40 min, 3=50 min, 4=60 min 20=20 min, 30=30 min (P), 40=40 min 50=50 min, 60=60 min 0=8 sec delay-start (P) 1=(system address ×1×8) sec delay-start 2=(system address ×2×8) sec delay-start 3=(system address ×3×8) sec delay-start

30=30 sec , 60=60 sec (P) ,,,,, 240=240 sec

5=5 min (P) , 10=10 min , 15=15 min , 20=20 min , 25=25 min 30=30 min

0=Invalid , 1=22 , 2=25 , 3=28 , 4=32 , 5=36 , 6=40 , 7=45 , 8=50 , 9=56 , 10=63 , 11=71 , 12=80 , 13=90 , 14=100 , 15=112 , 16=125 , 17=140 , 18=160 , 19=180 , 20=210 , 21=224 , 22=250 , 23=280 , 24=335 , 25=355 , 26=420 , 27=450 , 28=500 , 29=560 , 30=600 , 31=630 , 32=670 , 33=710 , 34=800 , 35=840 0=Invalid (P) 1=High static pressure mode 2-6=Never use 20=20min, 21=21min ,,,,, 40=40min (P) 41 - 90=Never use

0=Invalid (P), 1=Valid

Control Functions

1 - 48

Page 57

3WAY VRF SYSTEM

14. Detailed Settings in EEPROM of Outdoor Unit

Never use the DN code unlisted in the following table. (P) : Factory preset mode

DN Item Setting No.

Actuation of solenoid valve kit

(EP closed)

C1 O

CD Setting at heating thermostat OFF 0=Invalid (P) , 1=Heating airow prevention mode

output change

Indoor fan mode setting when in discharge tube accumulated refrigerant recovery control Discharge tube accumulated refrigerant recovery control permission temperature Discharge air temperature control with thermostat OFF additional time Indoor unit fan selection when in cooling thermostat OFF

0=Invalid (P), 1=Valid

0=Continuously set OFF (P) 1=Refrigerant leak prevention (normal OFF) 2=Refrigerant leak prevention (normal ON) 3=Pumpdown control

0=Invalid , 1=stop (P) , 2=LL

-25=-13°F (-25°C), -20=-4°F (-20°C), -15=5°F (-15°C) ,,,,, 40=104°F (40°C) ,,,,, 55=131°F (55°C)

-20=-20 min , -19=-19 min ,,,,, 0=0 min (P) ,,,,, 10=10 min 0=Invalid (P) , 1=stop , 2=LL , 3=interval operation , 4=never use

Control Functions

1 - 49

Page 58

PCB and Functions

1. Outdoor Unit Control PCB

PCB and Functions

1. Outdoor Unit Control PCB

RC1 plug (

CN75

)

Terminating resistance pin

HIC3(CN43

)

HIC7(CN78

)

HIC4(CN19

)

HIC8(CN85

)

HIC6(CN82

)

HIC5(CN80

)

HIC2(CN10

)

HIC1(CN7

)

Comp. discharge 1 sensor DISCH1(CN55

)

Comp. discharge 2 sensor DISCH2(CN56

)

Suction gas temp. SCG(CN77

)

Gas temp.sensor at heat exchanger 1, 2 EXG1,2(CN61

)

Liquid temp.sensor at heat exchanger 1, 2 EXL1,2(CN60

)

Suction temp. SCT(CN65

)

Outdoor air temp. TO(CN53)

Low-pressure sensor LPS(CN49

)

High-pressure



sensor HPS(CN46

)

MODE (

CN40) pin

A. ADD (

CN30) pin

DEF(CN25) pin

(

CN24) pin

STOP(CN28) pin

CHK(CN23) pin

TEST(CN22) pin

RUN(CN27) pin

SILENT(CN33

)

EEPROM memory IC

(

IC14

)

EEPROM LED (LED3

)

Alarm LED (

LED2

)

Alarm LED (

LED1

)

SW4

SW3

SW2

SW1

SW6

SW5

SW7

Snow sensor (

CN34

)

Oil detection sensor OIL1,2(CN54

)

(

CN67

)

15-2. Outdoor Unit Control PCB CR-144MF2U9 / A748187

(U-120MF2U9 / U-144MF2U9)

OC plug (

CN76

)

RC plug (

CN73

)

EMG plug (

CN69

)

15. Outdoor Unit Control PCB

15-1. Outdoor Unit Control PCB CR-72MF2U9 / A748186

(U-72MF2U9 / U-96MF2U9)

3WAY VRF SYSTEM

Control Functions

RC1 plug (

CN75

OC plug

(

CN76

RC plug

(

CN73

EMG plug

(

CN69

Terminating resistance pin (

)

CN67

)

HIC3(CN43

)

Alarm LED (

)

LED1

Alarm LED (

)

LED2

SW5

EEPROM LED (LED3

SW6

)

HIC4(CN19

HIC2(CN10

HIC1(CN7

Comp. discharge 1 sensor DISCH1(CN55

)

Suction gas temp. SCG(CN77

)

EEPROM memory IC

(

)

IC14

SW7

SW4

TEST(CN22) pin

CHK(CN23) pin

AP(CN24) pin

SW3

Snow sensor (

CN34

DEF(CN25) pin

RUN(CN27) pin

SILENT(CN33

STOP(CN28) pin

A. ADD (

)

Gas temp. sensor at heat exchanger 1, 2 EXG1,2(CN61

Outdoor air temp. TO(CN53)

)

Suction temp. SCT(CN65

)

Oil detection sensor OIL1,2(CN54

Liquid temp.sensor at heat exchanger 1, 2 EXL1,2(CN60

)

Low-pressure sensor LPS(CN49

High-pressure sensor HPS(CN46

)

SW2

SW1

CN30) pin

MODE (

CN40) pin

)

1 - 50

Page 59

PCB and Functions

1. Outdoor Unit Control PCB

15. Outdoor Unit Control PCB

15-2. Outdoor Unit Control PCB CR-144MF2U9 / A748187

(U-120MF2U9 / U-144MF2U9)

3WAY VRF SYSTEM

Control Functions

RC1 plug (

)

CN75

OC plug (

CN76

RC plug (

CN73

EMG plug (

)

CN69

EEPROM LED (LED3

Terminating resistance pin (

)

CN67

)

HIC7(CN78

)

HIC3(CN43

)

Alarm LED (

)

LED1

Alarm LED (

)

LED2

SW5

SW6

)

SW7

EEPROM memory IC

(

)

IC14

HIC8(CN85

HIC6(CN82

HIC5(CN80

HIC4(CN19

HIC2(CN10

HIC1(CN7

Comp. discharge 1 sensor DISCH1(CN55

)

Suction gas temp. SCG(CN77

SW4

SW3

SW2

SW1

Low-pressure sensor LPS(CN49

Snow sensor (

CN34

SILENT(CN33

RUN(CN27) pin

TEST(CN22) pin

CHK(CN23) pin

)

STOP(CN28) pin

(

CN24) pin

A. ADD (

CN30) pin

DEF(CN25) pin



MODE (

CN40) pin

)

High-pressure sensor HPS(CN46

)

Oil detection sensor OIL1,2(CN54

Comp. discharge 2

)

sensor DISCH2(CN56

Gas temp.sensor at heat exchanger 1, 2 EXG1,2(CN61

)

Outdoor air temp. TO(CN53)

Suction temp. SCT(CN65

1 - 51

Liquid temp.sensor at heat exchanger 1, 2

)

EXL1,2(CN60

Page 60

1. Outdoor Unit Control PCB

PCB and Functions

1. Outdoor Unit Control PCB

15-4. Outdoor Unit HIC PCB A747843

(U-72MF2U9 / U-120MF2U9 / U-144MF2U9)

VWNPU

V WUNP

15-5. Outdoor Unit HIC PCB A747846

(U-96MF2U9)

15. Outdoor Unit Control PCB

3WAY VRF SYSTEM

Control Functions

15-3. Outdoor Unit Control PCB ACXA73-02070

(

U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94

LPS(CN49)

HPS(CN46)

CN34 SW3

LED2

LED1

SW7

CN33

SW4

OIL1,2(CN54)

SW1SW2

DISCH1(CN55)

CN25

)

DISCH2(CN56)

CN24CN23CN22

TO(CN53)

EXL1,2(CN60)

EXG1,2(CN61)

SCT(CN65)

SCG(CN77)

CN40

CN30

CN28

CN27

SW6

SW5

1 - 52

CN67 CN69

CN82

Page 61

PCB and Functions

1. Outdoor Unit Control PCB

15. Outdoor Unit Control PCB

15-4. Outdoor Unit HIC PCB A747843

(U-72MF2U9 / U-120MF2U9 / U-144MF2U9)

3WAY VRF SYSTEM

Control Functions

15-5. Outdoor Unit HIC PCB A747846

(U-96MF2U9)

VWNPU

1 - 53

V WUNP

Page 62

1. Outdoor Unit Control PCB

PCB and Functions

A747842 A747845

(U-72MF2U9 / U-120MF2U9 / U-144MF2U9) (U-96MF2U9)

15-7. Outdoor Unit Filter PCB

1. Outdoor Unit Control PCB

ACXA73-02080

(U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94)

15. Outdoor Unit Control PCB

15-6. Outdoor Unit HIC PCB ACXA73-02090

(U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94)

3WAY VRF SYSTEM

Control Functions

W NUVUP NV NW

1 - 54

Page 63

PCB and Functions

1. Outdoor Unit Control PCB

15. Outdoor Unit Control PCB

15-7. Outdoor Unit Filter PCB

A747842 A747845

(U-72MF2U9 / U-120MF2U9 / U-144MF2U9) (U-96MF2U9)

3WAY VRF SYSTEM

Control Functions

ACXA73-02080

(U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94)

1 - 55

Page 64

PCB and Functions

1. Outdoor Unit Control PCB

PCB and Functions

(U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94)

15-9. Outdoor Unit Relay PCB ACXA73-02110

15. Outdoor Unit Control PCB

15-8. Outdoor Unit FAN PCB

A747844

(U-72MF2U9 / U-96MF2U9 / U-120MF2U9 / U-144MF2U9)

3WAY VRF SYSTEM

Control Functions

PWVUN

ACXA73-02100

(U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94)

1 - 56

Page 65

15. Outdoor Unit Control PCB

1. Outdoor Unit Control PCB

PCB and Functions

15-9. Outdoor Unit Relay PCB ACXA73-02110

(U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94)

3WAY VRF SYSTEM

Control Functions

1 - 57

Page 66

PCB and Functions

1. Outdoor Unit Control PCB

PCB and Functions

1. Outdoor Unit Control PCB

Terminating resistance pin (3P, Black) (CN67)

For communications circuit impedance matching

A connecting socket (2P, White) is attached to the terminating resistance pin at the time of shipment from the factory. In the case of link wiring which combines the inter-unit control wiring for multiple systems into a single communications circuit, when using, see the item “5. Auto Address Setting” under the section “6. TEST RUN”.

•

LED1, 2

LED 1 and 2 blink alternately while auto address setting is in progress. Display the alarm contents for alarms which were detected by the outdoor unit.

•

RUN pin (2P, White) (CN27)

Start pin

Short-circuit this pin and apply a pulse signal to start all indoor units in that refrigerant system.

STOP pin (2P, White) (CN28)

Stop pin

CHK pin (2P, White) When set to short-circuit, changes to test run mode.

(Test run mode is automatically cancelled after an hour.) When short-circuit is cancelled, test run mode is cancelled.

Short-circuit this pin and apply a pulse signal to stop all indoor units in that refrigerant system.

AP pin (2P, White) (CN24)

Vacuuming pin

To perform vacuuming of the outdoor unit, short-circuit this pin and then turn the power ON. All solenoid valves turn ON and vacuuming begins smoothly. (Do not perform auto address setting at this time.) Release the short-circuit to return the unit to normal status.

•

TEST pin (2P, White) (CN22)

(CN23)

This pin is used to test the PCB at the factory. When the power is turned ON after this pin has been short-circuited, all output signals will be output in sequence

DEF pin (2P, White) When the pin of the main unit is short-circuit in heating mode, defrosting operation is started.

Even if short circuited, defrosting will not be activated immediately.

(CN25)

SNOW plug (3P, Red)

Can be used when installing a snowfall sensor device.

(CN34)

SILENT plug (2P, White)

Can be used when setting the outdoor unit fan is sound absorbing mode.

(CN33)

. (Sequential output does not occur if this pin is short-circuited when

the power is already ON.) Releasing this pin returns the unit to normal control.

•

OC EMG terminal (3P, Black) (CN69)

If “TO INDOOR UNIT” accidently connected to high voltage, use the terminal base TM1. Method: 1. Replace the pins 1 and 2 of CN69 with the pins 2 and 3.

2. Disconnect JP11.

RC1 EMG terminal (3P, Black) (CN82)

If “TO OUTDOOR UNIT” accidently connected to high voltage, use the terminal base TM1. Method: 1. Replace the pins 1 and 2 of CN82 with the pins 2 and 3.

2. Disconnect JP12.

3WAY VRF SYSTEM

15. Outdoor Unit Control PCB

Control Functions

15-10. Functions

A. ADD pin (2P, White) (CN30)

Rotary switch (10 positions, Black)

DIP switch (2P, Black)

Rotary switch (10 positions, Red)

DIP switch (3P, Black) (For details concerning SW3 and SW4, see Table 2.)

SW5 DIP switch (3P, Black)

SW6 DIP switch (3P, Black)

DIP switch (4P, Black or 3P, Black)

Auto address setting pin

Short-circuit this pin for 1 second or longer to automatically set the addresses at the indoor

•

units that are connected to that outdoor unit and are within the same system. The system address is "1" at the time of shipment. Auto address setting is necessary even

•

for communications lines in a single system where the inter-unit control wiring does not cross to any other systems. While auto address setting is in progress, the 2 LEDs (LED1, 2: Red) on the outdoor unit

•

control PCB blink alternately. (Short-circuiting this pin while auto address setting is in progress will stop the auto address setting operation.)

Outdoor system address setting switchSW1

The setting is "1" at the time of shipment. It is not necessary to change the setting if wiring

•

is connected only to an outdoor unit and indoor units in a single system and the inter-unit control wiring does not cross multiple systems. If wiring links the inter-unit control wiring for multiple systems to the same communications

•

lines, then a different address must be set for each refrigerant tubing system. If wiring links multiple systems, a maximum of 30 systems (up to 64 indoor units) can be

•

connected. This setting can be set up to "39," however control will be for 30 systems even if the setting is set to higher than 30. An alarm will be displayed if system addresses are duplicated. (For details, see Table 1.)

Switches for setting system address 10s digit and 20s digitSW2

If 10 systems or more are set, the setting is made by a combination of this DIP switch and

•

SW1. If 10 - 19 systems are set, set switch 1 (10s digit) to ON.

•

If 20 - 29 systems are set, set switch 2 (20s digit) to ON, and set switch 1 (10s digit) to OFF.

•

If 30 systems are set, set both switch 1 (10s digit) and switch 2 (20s digit) to ON.

•

(For details concerning SW1 and SW2, see Table 1.)

Switch for setting the number of connected indoor units. In order to allow the outdoor unit to SW3

manage indoor units in the same refrigerant system, set the number of connected indoor units.

(For details, see Table 2.)

Switches for setting the 10s, 20s, and 30s digit for the number of connected indoor units SW4

Unit No. setting switch

The setting is "1" at the time of shipment. (For details, see Table 3.)•

Switch for setting the number of outdoor units

Turn the switches ON according to the number of outdoor units (1 - 3). (For details, see

•

Table 4.)

Backup operation switchSW7 If 1st compressor has malfunctioned, turn INV or INV1 ON and BACKUP SW ON to operate the outdoor unit using only 2nd compressor. If 2nd compressor has malfunctioned, turn INV2 / AC or INV2 ON and BACKUP SW ON to operate the outdoor unit using only 1st compressor.

1 - 58

Page 67

PCB and Functions

1. Outdoor Unit Control PCB

15. Outdoor Unit Control PCB

3WAY VRF SYSTEM

Control Functions

Terminating resistance pin (3P, Black) (CN67)

LED1, 2

RUN pin (2P, White) (CN27)

STOP pin (2P, White) (CN28)

AP pin (2P, White) (CN24)

TEST pin (2P, White) (CN22)

For communications circuit impedance matching

A connecting socket (2P, White) is attached to the terminating resistance pin at the time of

•

shipment from the factory. In the case of link wiring which combines the inter-unit control wiring for multiple systems

•

into a single communications circuit, when using, see the item “5. Auto Address Setting” under the section “6. TEST RUN”.

LED 1 and 2 blink alternately while auto address setting is in progress.

•

Display the alarm contents for alarms which were detected by the outdoor unit.

•

Start pin

Short-circuit this pin and apply a pulse signal to start all indoor units in that refrigerant system.

Stop pin

Short-circuit this pin and apply a pulse signal to stop all indoor units in that refrigerant system.

Vacuuming pin

To perform vacuuming of the outdoor unit, short-circuit this pin and then turn the power ON.

•

All solenoid valves turn ON and vacuuming begins smoothly. (Do not perform auto address setting at this time.) Release the short-circuit to return the unit to normal status.

•

This pin is used to test the PCB at the factory.

•

When the power is turned ON after this pin has been short-circuited, all output signals will be output in sequence the power is already ON.) Releasing this pin returns the unit to normal control.

. (Sequential output does not occur if this pin is short-circuited when

CHK pin (2P, White) When set to short-circuit, changes to test run mode. (CN23)

DEF pin (2P, White) When the pin of the main unit is short-circuit in heating mode, defrosting operation is started. (CN25)

SNOW plug (3P, Red) (CN34)

SILENT plug (2P, White) (CN33)

OC EMG terminal (3P, Black) (CN69)

RC1 EMG terminal (3P, Black) (CN82)

(Test run mode is automatically cancelled after an hour.) When short-circuit is cancelled, test run mode is cancelled.

Even if short circuited, defrosting will not be activated immediately.

Can be used when installing a snowfall sensor device.

Can be used when setting the outdoor unit fan is sound absorbing mode.

If “TO INDOOR UNIT” accidently connected to high voltage, use the terminal base TM1. Method: 1. Replace the pins 1 and 2 of CN69 with the pins 2 and 3.

2. Disconnect JP11.

If “TO OUTDOOR UNIT” accidently connected to high voltage, use the terminal base TM1. Method: 1. Replace the pins 1 and 2 of CN82 with the pins 2 and 3.

2. Disconnect JP12.

1 - 59

Page 68

PCB and Functions

1. Outdoor Unit Control PCB

15. Outdoor Unit Control PCB

Table 1. Setting the System Address

[SW1: Rotary switch (Black), SW2: 2P DIP (Black)]

Outdoor system address

1 refrigerant system only

Link wiring

Table 2. Setting the Number of Indoor Units

[SW3: Rotary switch (Red), SW4: 3P DIP (Black)]

Number of Indoor Units

1 2 3

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16 17 18 19

SW3 Setting

SW1 setting

1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9

1 2 3

SW2 setting

(10s digit)

OFF

OFF OFF OFF OFF OFF OFF OFF OFF OFF

ON ON ON ON ON ON ON ON ON ON

SW4 Setting

1 2 3 OFF OFF OFF

OFF OFF OFF

(20s digit)

OFF

OFF OFF OFF OFF OFF OFF OFF OFF OFF OFF OFF OFF OFF OFF OFF OFF OFF OFF OFF

OFF OFF OFF

Outdoor system address

20 21 22 23 24

Link wiring

Table 3. Setting the Outdoor Unit address [SW5: DIP switch (Black)]

Outdoor Unit

Address

1 2 3

25 26 27 28 29 30

OFF

SW1 setting

0 1 2 3 4 5 6 7 8 9 0

SW5 Setting

1 2 3

3WAY VRF SYSTEM

Control Functions

SW2 setting

(10s digit)

OFF OFF OFF OFF OFF OFF OFF OFF OFF OFF

OFF

ON ON

(20s digit)

ON ON ON ON ON ON ON ON ON ON ON

OFF OFF OFF

10 11

19 20 21

29 30 31

39 40 41

49 50 51 52

9 0 1

9 0 1 2

OFF

ON ON

ON OFF OFF

OFF OFF OFF

OFF

ON OFF OFF OFF

OFF OFF OFF

OFF

ON ON

ON OFF OFF

OFF OFF OFF

OFF

OFF OFF OFF

OFF

ON ON

ON ON ON

ON ON ON ON

Table 4. Setting the Number of Outdoor Units

[SW6: DIP switch (Black)]

Number of Outdoor Units

1 2 3

1 - 60

1 2 3

OFF

SW6 Setting

OFF

ON ON

OFF OFF OFF

Page 69

Contents

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

2. OUTDOOR UNIT REPAIR PROCEDURES

3WAY VRF SYSTEM

1. -2

Removing Panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2. -4

Discharging Compressor Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3. -7

Backup Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Recovering Refrigerant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5. -14

Checking for Leakage After Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6. -15

Evacuating System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Charging Compressor Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8. -22

Pumping Out Refrigerant from Outdoor Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9. -26

Compressor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10. 2

Replacing Peripheral Parts of Fusible Plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

High and Low Pressure Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11. -37

-9

-16

-36

2 - 1

Page 70

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

1. Removing Panels

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

1. Removing Panels

Fig. 1-c

Fig. 1-d

Type: 72, 96

Type: 120, 144

U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94

Upper side front panel

Lower side front panel

Power outlet panel

Tubing cover

Mounting Plate

Power outlet panel

Tubing cover

Lower side front panel

Upper side front panel

Mounting Plate

1. Removing Panels

3WAY VRF SYSTEM

Outdoor Unit Repair Procedures

(1) Front panels removal

(2) Power outlet panel & tubing cover removal

CAUTION

• Remove 2 front (upper and lower) panels.

• Remove the power outlet panel.

• Remove the tubing cover.

U-72MF2U9 / U-96MF2U9 / U-120MF2U9 / U-144MF2U9

Type: 72, 96

Be sure to turn off the power before maintenance work. Then start working when 5 minutes or longer has passed after turning off the power.

Upper side front panel

Lower side front panel

Mounting Plate

Type: 120, 144

Upper side front panel

Lower side front panel

Tubing cover

Power outlet panel

Fig. 1-a

Tubing cover

Power outlet panel

Mounting Plate

Fig. 1-b

2 - 2

Page 71

1. Removing Panels

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

1. Removing Panels

3WAY VRF SYSTEM

Outdoor Unit Repair Procedures

U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94

Type: 72, 96

Upper side front panel

Type: 120, 144

Lower side front panel

Mounting Plate

Tubing cover

Power outlet panel

Fig. 1-c

Upper side front panel

Lower side front panel

Power outlet panel

Mounting Plate

Tubing cover

Fig. 1-d

2 - 3

Page 72

3WAY VRF SYSTEM

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

2. Discharging Compressor Oil

Outdoor Unit Repair Procedures

Sampling of discharged oil can be used for checking the condition of the system. Based on the appearance and color of the discharged oil, a judgment can be made on whether the system is operating normally or not.

2-1. Discharging Oil from Oil Separator

Recover the refrigerant from the outdoor unit following the procedure given in “4. Recovering Refrigerant”.

In the case of 1 outdoor unit in a system Open the balance tube using the flathead screwdriver.

In the case of more than 2 outdoor units in a system

Close other outdoor unit balance valves. Install hoses as indicated on the equipment and feed nitrogen gas gradually to provide pressure to the system from the low-pressure outlet and collect oil in a pan or container. (Figs. 2-a, 2-b, 2-c and 2-d)

The low-pressure outlet port is nearly at the center area in the unit.

CAUTION

U-72MF2U9 / U-96MF2U9 / U-120MF2U9 / U-144MF2U9

Nitrogen gas

A faulty outdoor unit may remain pressurized. The oil outlet port employs a Schrader-type push-to-release valve. Be careful to avoid accidental oil release when using the port.

Type: 72, 96

Manifold gauge

Lo Hi

Packless valve or the like

Container

Low-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

High-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

Oil balance tube service port (For ø5/16” (ø7.94mm)-dia connector)

Liquid tube service port (for ø5/16” (ø7.94mm)-dia connector)

Discharge tube service port (for ø5/16” (ø7.94mm)-dia connector)

Suction tube service port (for ø5/16” (ø7.94mm)-dia connector)

Fig. 2-a

Nitrogen gas

Type: 120, 144

Manifold gauge

Lo Hi

Container

Packless valve or the like

Low-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

High-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

Oil balance tube service port (For ø5/16” (ø7.94mm)-dia connector)

Liquid tube service port (for ø5/16” (ø7.94mm)-dia connector)

Suction tube service port (for ø5/16” (ø7.94mm)-dia connector)

Discharge tube service port (for ø5/16” (ø7.94mm)-dia connector)

Fig. 2-b

2 - 4

Page 73

2. Discharging Compressor Oil

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

2. Discharging Compressor Oil

U-72MF2U94 / U-96MF2U94 / U-120MF2U94 / U-144MF2U94

Type: 72, 96

3WAY VRF SYSTEM

Outdoor Unit Repair Procedures

Low-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

High-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

Oil balance tube service port (For ø5/16” (ø7.94mm)-dia connector)

Nitrogen gas

Manifold gauge

Lo Hi

Container

Type: 120, 144

Manifold gauge

Lo Hi

Container

Packless valve or the like

Liquid tube service port (for ø5/16” (ø7.94mm)-dia connector)

Discharge tube service port (for ø5/16” (ø7.94mm)-dia connector)

Suction tube service port (for ø5/16” (ø7.94mm)-dia connector)

Fig. 2-c

Low-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

High-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

Oil balance tube service port (For ø5/16” (ø7.94mm)-dia connector)

Liquid tube service port (for ø5/16” (ø7.94mm)-dia connector)

Suction tube service port (for ø5/16” (ø7.94mm)-dia connector)

Discharge tube service port (for ø5/16” (ø7.94mm)-dia connector)

2 - 5

Fig. 2-d

Page 74

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

2. Discharging Compressor Oil

3-1. Automatic Backup

This system includes an emergency automatic backup function that allows the air conditioner to operate during the period after trouble occurs until repairs are made. However, during repair and at other times, use manual backup operation.

For details, see the item “12. Backup Operation” under the section 1.

3-2. Manual Backup

3-2-1. Backup operation by disconnecting the outdoor unit (1) Changing the outdoor unit control PCB settings

This backup operation is the conventional method of backup operation. It involves disconnecting the failed outdoor unit from the system, and operating only the normal outdoor units. For details, see “(2) Manual Backup Operation” of “12. Backup Operation” under the section 1.

After the alarm details are sent to the control device, control for automatic backup operation begins when the ON/OFF button of the wired remote controller is pressed again (operation is started after the alarm is cleared). During this operating mode, “ ” blinks on the wired remote controller only to inform the user that operation is in backup mode. However, this is not displayed on any other control devices.

Backup operation is intended as emergency operation until repairs are completed. Have repairs made as soon as possible.

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

3. Backup Operation

If the power is not reset on the control PCB of the No. 1 outdoor unit (main unit), backup mode operation will continue after the repairs are completed.

In order to cancel automatic backup mode, it is necessary to reset the power of all the outdoor units in the

system.

Settings at No. 1 unit (main unit)

Settings at normal outdoor units other than the No. 1 unit

No particular changes

Settings at the failed outdoor unit

No particular changes However, close all service valves (suction tube, discharge tube, liquid tube, and balance tube) at the failed outdoor unit, and disconnect the communication wiring between the outdoor units.

Action

No change

Subtract the number of failed units from the current setting.

Switch on outdoor unit control PCB

System address (SW2, SW1)

No. of indoor units (SW4, SW3)

No. of outdoor units (SW6)

Outdoor unit No. (SW5) No change

CAUTION

3WAY VRF SYSTEM

2. Discharging Compressor Oil

2-2. Discharging Oil in Compressor

Recover the refrigerant in the outdoor unit following the procedures in “4. Recovering Refrigerant.” Remove the compressor and discharge the oil in it. See “9. Compressor” for detailed procedures.

2-3. Checking the Oil

Acceptance/rejection criteria for the oil

Condition of

refrigeration cycle

It is difficult to measure the total acid value in the field, therefore oil hue and odor are the rule of thumb.

Checking for carbon deposits and abrasive metal powder can additionally be used to assess the system condition.

Normal Yellowish None 0.02 or less 3.5 or less

Abnormal overheat-

operation

Motor burnout

Color Odor Total acid value Hue

Brownish

Brownish /

blackish

Condition of oil

Smells somewhat

(not as strong as below)

Pungent / burnt odor

Outdoor Unit Repair Procedures

Judgment criteria for changing oil*

0.06 or over 4.0 or over

Changing the oil and system cleaning with dry-cores are necessary.

2 - 6

Page 75

3WAY VRF SYSTEM

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

3. Backup Operation

Outdoor Unit Repair Procedures

3-1. Automatic Backup

For details, see the item “12. Backup Operation” under the section 1.

In order to cancel automatic backup mode, it is necessary to reset the power of all the outdoor units in the

system.

CAUTION

Backup operation is intended as emergency operation until repairs are completed. Have repairs made as soon as possible.

3-2. Manual Backup

3-2-1. Backup operation by disconnecting the outdoor unit (1) Changing the outdoor unit control PCB settings

Settings at No. 1 unit (main unit)

Switch on outdoor unit control PCB

System address (SW2, SW1)

No. of indoor units (SW4, SW3)

No. of outdoor units (SW6)

Outdoor unit No. (SW5) No change

If the power is not reset on the control PCB of the No. 1 outdoor unit (main unit), backup mode operation will continue after the repairs are completed.

Action

No change

Subtract the number of failed units from the current setting.

Settings at normal outdoor units other than the No. 1 unit

No particular changes

Settings at the failed outdoor unit

2 - 7

Page 76

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

3. Backup Operation

4-1. Refrigerant Recovery Procedures (from Outdoor Units)

The following equipment and tools are required:

Jumper wire with clips, adjustable wrench, set of manifold gauge valves specially designed for refrigerant R410A only, vacuum pump, refrigerant recovery unit, pre-purged refrigerant cylinder for recovery, flathead screwdriver, and outdoor unit maintenance remote controller.

(1) Turn off the power of the outdoor unit beforehand (at power mains).

(2) Fully close all the service valve of the outdoor unit.

(3) Connect the outdoor unit’s high-pressure and low-pressure outlet ports with the Hi and Lo sides of the manifold

gauge valves using hoses. (Figs. 3-a, 3-b)

(4) Connect the manifold gauge valves, refrigerant recovery unit, and recovery cylinder using hoses.

To avoid the entry of air into the refrigerant tube, carry out this connection work carefully. (Figs. 3-a, 3-b)

(5) Locate the AP pin (CN24) on the control PCB in the faulty outdoor unit and short them using the clips of

the jumper wire. Then restore electrical power to the outdoor unit.

(6) Carry out refrigerant recovery.

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

4. Recovering Refrigerant

The remaining refrigerant in the faulty outdoor unit may create internal pressure. Before connecting hoses, be sure to confirm that each of the manifold gauge valves is tightly closed. Note that the connection ports employ Schrader-type push-to-release valves.

CAUTION

For detailed procedures such as connecting the refrigerant recovery unit with the recovery cylinder and methods used for recovery, follow the specific instructions that came with the refrigerant recovery unit.

CAUTION

By short-circuiting the AP pin (CN24), each solenoid valve in the outdoor unit is forcibly opened as soon as power comes on, which releases all remaining refrigerant into the recovery cylinder. Since neglecting this procedure may leave some refrigerant in the system, it is important that you carry out this step.

CAUTION

To determine the completion of refrigerant recovery, follow the instructions that CAUTION came with the refrigerant recovery unit.

CAUTION

Type: 72, 96

High-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

Low-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

Liquid tube service port (for ø5/16” (ø7.94mm)-dia connector)

Discharge tube service port (for ø5/16” (ø7.94mm)-dia connector)

Suction tube service port (for ø5/16” (ø7.94mm)-dia connector)

Oil balance tube service port (For ø5/16” (ø7.94mm)-dia connector)

Fig. 3-a

Lo Hi

Refrigerant recovery unit

Manifold

gauge

Refrigerant recovery cylinder

3WAY VRF SYSTEM

3. Backup Operation

(2) Adjusting the refrigerant for backup operation

CAUTION

During backup operation, all of the service valves on the failed unit are closed. However, if a check of the backup operating conditions shows that the level of gas is low, recover the refrigerant from the failed outdoor unit. If the level of gas is too high, collect refrigerant at the failed outdoor unit.

Recovering refrigerant

With the normal outdoor units operating, monitor the operating condition and open/close the suction tube service valve on the failed outdoor unit where all the service valves were closed. In this way, recover refrigerant from the failed outdoor unit in order to adjust the amount of refrigerant in the system. After adjusting the amount of refrigerant, close the suction tube valve at the failed outdoor unit.

Collecting refrigerant in the failed outdoor unit

Short-circuit the AP pin (CN24) on the control PCB of the failed outdoor unit where the service valves are closed, then turn the power ON. Also disconnect the wiring between the outdoor units.

With the normal outdoor units operating, monitor the operating condition and open/close the liquid tube service valve on the failed outdoor unit where all the service valves were closed. In this way, collect refrigerant in the failed outdoor unit in order to adjust the amount of refrigerant in the system.

After adjusting the amount of refrigerant, turn OFF the power at the failed outdoor unit, release the shortcircuit at the AP pin (CN24), and close the liquid tube valve at the failed outdoor unit.

* Refrigerant recovery is not affected by the power status of the failed outdoor unit. However, collecting

refrigerant in the failed outdoor unit is affected by whether the power at that outdoor unit can be turned ON. If the power cannot be turned ON, use a refrigerant recovery device and recover the refrigerant into a recovery cylinder in order to adjust the amount of refrigerant in the system.

After recovery work is completed, wire the communication lines between indoor and outdoor units again. If it not finished yet, an alarm is emitted immediately.

Outdoor Unit Repair Procedures

2 - 8

Page 77

3WAY VRF SYSTEM

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

4. Recovering Refrigerant

Outdoor Unit Repair Procedures

The following equipment and tools are required:

4-1. Refrigerant Recovery Procedures (from Outdoor Units)

(1) Turn off the power of the outdoor unit beforehand (at power mains).

(2) Fully close all the service valve of the outdoor unit.

(3) Connect the outdoor unit’s high-pressure and low-pressure outlet ports with the Hi and Lo sides of the manifold

gauge valves using hoses. (Figs. 3-a, 3-b)

The remaining refrigerant in the faulty outdoor unit may create internal pressure.

CAUTION

(4) Connect the manifold gauge valves, refrigerant recovery unit, and recovery cylinder using hoses.

To avoid the entry of air into the refrigerant tube, carry out this connection work carefully. (Figs. 3-a, 3-b)

CAUTION

Before connecting hoses, be sure to confirm that each of the manifold gauge valves is tightly closed. Note that the connection ports employ Schrader-type push-to-release valves.

(5) Locate the AP pin (CN24) on the control PCB in the faulty outdoor unit and short them using the clips of

the jumper wire. Then restore electrical power to the outdoor unit.

By short-circuiting the AP pin (CN24), each solenoid valve in the outdoor unit is forcibly

CAUTION

(6) Carry out refrigerant recovery.

CAUTION

opened as soon as power comes on, which releases all remaining refrigerant into the recovery cylinder. Since neglecting this procedure may leave some refrigerant in the system, it is important that you carry out this step.

To determine the completion of refrigerant recovery, follow the instructions that CAUTION came with the refrigerant recovery unit.

Type: 72, 96

Low-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

High-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

Oil balance tube service port (For ø5/16” (ø7.94mm)-dia connector)

Manifold

gauge

Lo Hi

Liquid tube service port (for ø5/16” (ø7.94mm)-dia connector)

Refrigerant recovery unit

Refrigerant recovery cylinder

2 - 9

Discharge tube service port (for ø5/16” (ø7.94mm)-dia connector)

Suction tube service port (for ø5/16” (ø7.94mm)-dia connector)

Fig. 3-a

Page 78

3WAY VRF SYSTEM

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

4. Recovering Refrigerant

4-2-1. Cooling operation (for all units)

(CHECK)

button for 4 seconds or longer.)

(1) If the remote controller is used for maintenance of the outdoor unit

4-2-2. Refrigerant recovery procedures (1) (using indoor unit ball valve)

(1) If a ball valve with a service port has been provided in the indoor unit as shown in Fig. 4, follow the instructions

given in (2) through (7) below. If the service port is instead located in the outdoor side, follow the instructions in “4-2-3. Refrigerant recovery procedures (2)”.

(3) After running the unit in Cooling mode for about 5 minutes as described in “4-2-1. Cooling operation (for all

units)”, fully close the liquid tube ball valve.

(4) Run the unit in Cooling mode for 10 to 20 minutes more.

(2) Close the discharge tube ball valve.

(7) Recover the remaining refrigerant from the

indoor unit using the refrigerant recovery unit.

(5) Fully close the suction tube ball valve, and stop the operation of all units.

(6) Use hoses to connect the manifold gauge valves, refrigerant recovery unit, and refrigerant recovery cylinder

with each other. (Fig. 4) Do each connection quickly to prevent air from entering the tube.

(2) If the remote controller is not available for maintenance of the outdoor unit.

1. Connect the outdoor unit maintenance remote controller to the RC connector (3P) (BLU) (CN73) on any one of the outdoor unit control PCBs. Then start a test run of all units. (Press and hold the

1. Determine the outdoor unit where the unit No. setting (SW5) (3P DIP switch) (Blue) on the outdoor unit control PCB is set to No. 1.

3. Short-circuit the CHK pin (CN23) on the PCB to start test run operation.

2. Short-circuit the MODE pin (“COOL” side of CN40) on the main outdoor unit control PCB.

2. Press the See the Section 3 for the detail of the outdoor maintenance remote controller operation.

It may be possible to determine whether operation is cooling or heating by touching the suction tube or discharge tube. Cooling : low temperature (68 °F (20 °C) or lower) Heating : high temperature (140 °F (60 °C) or higher)

(MODE) button and change to cooling operation and ensure that the cooling is performed.

The discharge tube becomes hot (140 °F (60 °C) or higher) in heating mode. Be careful so as not to be burnt when touching the tube.

CAUTION

Remaining refrigerant may create internal pressure, therefore care should be taken when connecting the hoses.

CAUTION

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

4. Recovering Refrigerant

NOTE

To determine completion of refrigerant recovery, follow the instructions that came with the refrigerant recovery unit.

Fig. 4

Solenoid

valve kit

Indoor uni

Ball valve (separately purchased) Service port

Outdoor

unit

side

Suction tube

Discharge tube

Liquid tube

Manifold

gauge

Refrigerant

recovery

unit

Solenoid valve kit

Refrigerant recovery cylinder

4. Recovering Refrigerant

Outdoor Unit Repair Procedures

Type: 120, 144

Low-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

High-pressure outlet port (for ø5/16” (ø7.94mm)-dia connector)

Manifold

gauge

Lo Hi

Oil balance tube service port (For ø5/16” (ø7.94mm)-dia connector)

Liquid tube service port (for ø5/16” (ø7.94mm)-dia connector)

Refrigerant recovery unit

Suction tube service port (for ø5/16” (ø7.94mm)-dia connector)

Discharge tube service port (for ø5/16” (ø7.94mm)-dia connector)

Refrigerant recovery cylinder

4-2. Refrigerant Recovery Procedures (Indoor Unit)

The flowchart below shows the refrigerant recovery procedures you must follow when replacing or repairing the indoor unit due to trouble in the refrigerant circuit.

START

4-2-1. Cooling operation (for all units)

4-2-2. Refrigerant recovery procedures (1)

Ball valve is provided

in the indoor unit

YES

Turn off all equipment in system

When

replacing or repairing

a faulty unit, let other normal indoor

units run (excluding indoor unit where

can independently be turned off

for indoor unit where refrigerant is

refrigerant is

recovered)

Power

recovered

YES

Change controllable number of indoor units (including

changes in group control and integrated-control settings)

Other indoor units can operate normally

Replace or repair faulty unit

Check for leakage in repaired unit H*

Evacuate air from repaired unit H*

Charge refrigerant in repaired unit H* (Amount of charge

should equal that recovered by refrigerant recovery unit)

Change controllable number of indoor units (including

changes in group control and integrated-control settings)

Open ball valve

Ready for normal operation

END

4-2-3. Refrigerant

recovery procedures (2)

Figs. 2-a, 2-b, 2-c and 2-d

Modify power to permit

turning off power to

refrigerant-recovered

indoor units independently

Service work performed on indoor units is done simultaneously using the service ports at the liquid tube side, suction tube side and discharge tube side ball valves. Refer to each section in the

Turn off all equipment in system

Replace or repair faulty unit

Check for leakage in repaired unit

Evacuate air from repaired unit

Charge refrigerant in repaired unit

(Amount of charge should equal that

recovered by refrigerant recovery unit)

Ready for operation

Replace or repair faulty unit

Check for leakage in repaired unit H*

Evacuate air in repaired unit H*

Charge refrigerant in repaired unit H* (Amount of charge should equal that

recovered by refrigerant recovery unit)

Ready for normal operation

“Installation Instructions” on refrigerant charging, leak checking, and evacuation procedures.

2 - 10

Fig. 3-b

END

Open the ball valve

END

Page 79

3WAY VRF SYSTEM

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

4. Recovering Refrigerant

4-2-1. Cooling operation (for all units)

(1) If the remote controller is used for maintenance of the outdoor unit

1. Connect the outdoor unit maintenance remote controller to the RC connector (3P) (BLU) (CN73) on any one of the outdoor unit control PCBs. Then start a test run of all units. (Press and hold the

button for 4 seconds or longer.)

Outdoor Unit Repair Procedures

(CHECK)

2. Press the See the Section 3 for the detail of the outdoor maintenance remote controller operation.

CAUTION

(2) If the remote controller is not available for maintenance of the outdoor unit.

1. Determine the outdoor unit where the unit No. setting (SW5) (3P DIP switch) (Blue) on the outdoor unit control PCB is set to No. 1.

2. Short-circuit the MODE pin (“COOL” side of CN40) on the main outdoor unit control PCB.

3. Short-circuit the CHK pin (CN23) on the PCB to start test run operation.

4-2-2. Refrigerant recovery procedures (1) (using indoor unit ball valve)

(1) If a ball valve with a service port has been provided in the indoor unit as shown in Fig. 4, follow the instructions

given in (2) through (7) below. If the service port is instead located in the outdoor side, follow the instructions in “4-2-3. Refrigerant recovery procedures (2)”.

(2) Close the discharge tube ball valve.

(3) After running the unit in Cooling mode for about 5 minutes as described in “4-2-1. Cooling operation (for all

units)”, fully close the liquid tube ball valve.

(4) Run the unit in Cooling mode for 10 to 20 minutes more.

(5) Fully close the suction tube ball valve, and stop the operation of all units.

(6) Use hoses to connect the manifold gauge valves, refrigerant recovery unit, and refrigerant recovery cylinder

with each other. (Fig. 4) Do each connection quickly to prevent air from entering the tube.

(MODE) button and change to cooling operation and ensure that the cooling is performed.

The discharge tube becomes hot (140 °F (60 °C) or higher) in heating mode. Be careful so as not to be burnt when touching the tube.

CAUTION

(7) Recover the remaining refrigerant from the

indoor unit using the refrigerant recovery unit.

NOTE

To determine completion of refrigerant recovery, follow the instructions that came with the refrigerant recovery unit.

Remaining refrigerant may create internal pressure, therefore care should be taken when connecting the hoses.

Ball valve (separately purchased) Service port

Outdoor

unit

side

Refrigerant

recovery

Refrigerant recovery cylinder

2 - 11

Discharge tube

unit

Suction tube

Liquid tube

Manifold

gauge

Solenoid valve kit

Indoor uni

Solenoid

valve kit

Fig. 4

Page 80

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

4. Recovering Refrigerant

2WAY VRF SYSTEM

Outdoor Unit Repair Procedures

4. Recovering Refrigerant

(1) Turn off power to the entire outdoor system.

(3) If any unit has encountered a power failure, follow the instructions in “4-1. Refrigerant Recovery Procedures

(from Outdoor Units)” and perform refrigerant recovery for the faulty outdoor unit.

(4) Connect the manifold gauge to the high- and low-pressure outlet ports (Schrader-type valves) on any outdoor

unit. (Figs. 5-a, 5-b)

* If only a single outdoor unit is installed, the balance tube is not used. Therefore, leave this valve closed.

(5) Connect the manifold gauge valves, refrigerant recovery unit, and refrigerant recovery cylinder. Quickly connect

each part to prevent air from entering the tube.

(6) Check that each service valve of the suction tube, discharge tube, liquid tube, and the balance tube for the

outdoor unit has opened, then perform refrigerant recovery.

(2) Short-circuit the AP pin (CN24) on the outdoor control PCB of all outdoor units, then supply power to the

outdoor units. * By short-circuiting the AP pin (CN24) and supplying power to the outdoor units, the solenoid valve in each

unit is forcibly opened and all remaining refrigerant can be recovered.

Remaining refrigerant may cause internal pressure. Check that each valve on the manifold gauge valves is tightly closed. The connection port uses a Schrader-type push-to-release valve.

CAUTION

NOTE

To determine the completion of refrigerant recovery, follow the instructions that came with the refrigerant recovery unit.

4-3. Recovery of Refrigerant from Entire System