Mitsubishi PUD-P250YMF-C, PFD-P500VM-A, PFD-P250VM-A Service Manual

AIR CONDITIONERS CITY MULTI

Models < Outdoor unit >

PUD-P250YMF-C

< Iutdoor unit >

PFD-P250VM-A
PFD-P500VM-A

Service Handbook

Service Handbook PUD-P250YMF-C

PFD-P250VM-A
PFD-P500VM-A

Issued in Jun. 2004 MEE03K207-A
Printed in Japan

New publication effective Jun.2004
Specifications subject to change without notice.

HEAD OFFICE: MITSUBISHI DENKI BLDG., 2-2-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN

Service Handbook Close Control PUD-P250YMF-C/PFD-P250, P500VM-A

- 1 -

Contents

Please Read Before Servicing the Unit

1 Check Before Servicing the Unit .................................................. 8

[1]

Find out the model type and refrigerant type of the unit to be serviced

.. 8

[2] Principal System Components .............................................. 8

[3] Check the symptoms of the unit requiring service ................ 9

[4]

Be sure to read Read Before Servicing at the beginning of this manual

.. 9

[5] Prepare necessary tools ........................................................ 9

[6] If the refrigerant circuit is opened (to repair gas leak etc.),

the drier needs to be replaced .............................................. 9

[7]

Preparing the connecting pipes: When relocating or replacing

the unit, find out what types of refrigerant is used for the unit

.... 9

[8]

If there is a gas leak or if the remaining refrigerant is exposed to an open flame,

a noxious gas hydrofluoric acid may form. Provide adequate ventilation

.......... 9

2 Necessary Tools and Materials.................................................... 10

[1]

List of Tools and Materials Necessary for Units that Use R407C

(and adaptability of tools that have been used with units that use R22)

...... 10

3 Piping Materials .......................................................................... 11

4 Storage of Piping Materials.......................................................... 12

[1] Storage Location .................................................................... 12

[2] Pipe sealing before storage.................................................... 12

5 Machining Pipes .......................................................................... 13

6 Brazing ........................................................................................ 14

7 Testing Air Tightness.................................................................... 15

8 Vacuum Drying (Evacuating) ...................................................... 16

9 Charging the Circuit with Refrigerant .......................................... 17

0 What to Do When Refrigerant Leaks .......................................... 19

A Replacing the Drier ...................................................................... 19

11

. Restrictions

1 System Restrictions and System Configuration .......................... 20

[1] Switch Setting ........................................................................ 20

2 Restrictions on Transmission Lines.............................................. 22

[1] Electrical Wiring ...................................................................... 22

3 Restrictions on Refrigerant Pipe Length ...................................... 38

[1] Refrigerant Piping .................................................................. 38

22

. Components of the Unit

1 Internal Structure ........................................................................ 39

2 Control Box .................................................................................. 42

3 Main Board .................................................................................. 44

33

. Electrical Wiring Diagrams

1 Outdoor Unit ................................................................................ 49

2 Indoor Unit.................................................................................... 50

44

. Refrigerant Circuit

1 Refrigerant Circuit Diagram ........................................................ 52

2 List of Major Component Functions ............................................ 53

- 2 -

55

. Control

1 Dip Switch Functions and Factory Settings ................................ 56

[1] Outdoor Unit .......................................................................... 56

[2] Indoor Unit .............................................................................. 57

2 Controlling the Outdoor Unit ........................................................ 58

[1] Initial Control .......................................................................... 58

[2] Control at startup .................................................................... 58

[3] Bypass control ........................................................................ 58

[4] Frequency Control .................................................................. 59

[5] Oil-Return Control .................................................................. 60

[6] Outdoor Unit Fan .................................................................... 60

[7] Subcool Coil Control (Linear Expansion Valve (LEV1)).......... 60

[8] Circulating composition sensor (CS circuit)............................ 60

[9] Emergency Operation Mode .................................................. 61

[10]

Capacity Control Between Outdoor Units (For P500 Type Only)

.. 61

[11] Control-Block Diagram.......................................................... 62

[12] Operation Modes .................................................................. 62

3 Controlling the Indoor Unit .......................................................... 63

[1] Thermostat Functions ............................................................ 63

[2] Actuator Control...................................................................... 64

[3] Temperature Setting Range.................................................... 64

[4] Emergency Operation Mode .................................................. 64

[5] Three-minute restart-suspension mode.................................. 65

[6] Anti-Freeze Control ................................................................ 65

[7] Operation during Electrical Power Failure .............................. 65

4 Operation Flow Chart .................................................................. 66

[1] Mode Selection Flow Chart .................................................... 66

[2] Operation in each Mode ........................................................ 68

66

. Refrigerant Amount Adjustment

1 Operating Characteristics and Refrigerant Amount .................... 69

[1] Operating Characteristics/Refrigerant Amount ...................... 69

2 Checking and Adjusting Refrigerant Amount .............................. 69

[1] Symptoms .............................................................................. 69

[2] Refrigerant Volume ................................................................ 69

[3] Amount of Refrigerant to Be Added ...................................... 70

3 Refrigerant-Adjustment Operation Mode .................................... 71

[1] Procedures (only for air-cooled outdoor units) ...................... 71

77

. Troubleshooting

1 List of Check Code ...................................................................... 73

2 Intermittent Fault Check Code (outdoor units only) .................... 74

3 Self-Diagnosis and Problem-Solving Using Check Codes .......... 75

[1] Mechanical.............................................................................. 75

[2] Communication / System........................................................ 86

[3] System error .......................................................................... 93

[4] Troubleshooting using information on problems

with Remote Control, Input from External Source ................ 95

4 Transmission Wave Pattern and Noise Check ............................ 99

[1] M-NET Transmission .............................................................. 99

[2] MA Remote Controller Transmission ...................................... 100

5 Troubleshooting............................................................................ 102

[1] Principal Parts ........................................................................ 102

- 3 -

88

. LED Monitor Display

1 How to Read the Service Monitor LED........................................ 115

[1] How to read the LED .............................................................. 115

[2] Outdoor Unit Control LED Monitor.......................................... 116

99

. Test Run

1 Before a Test Run ........................................................................ 124

2 Test-Run Method.......................................................................... 124

3 Not to Be Alarmed When the Following Symptoms Appear........ 125

4 Standard Operation (reference data) .......................................... 126

[1] Cooling Operation .................................................................. 126

[2] Operation under Other Conditions.......................................... 126

00

. When Refrigerant Leaks

1 Repairing Leaks: Preparation, making repairs, and recharging

the system with refrigerant .......................................................... 127

[1] Location of leaks: Extension piping or indoor unit.................. 127

[2] Location of leaks: Outdoor unit .............................................. 127

0011

. Circulating Composition Analysis

1 Check the Composition of the Refrigerant .................................. 128

- 4 -

Warning

Safety Precautions

Warning: Failure to follow all instructions may result in serious personal injury or death.

Caution: Failure to follow all instructions may result in personal injury or damage to the unit.

sAfter reading this handbook, hand it over to those who will be using the unit.
sThe user of the unit should keep this manual at hand and make it available to those who will be

performing repairs, to those who will be relocating the unit, and to new users.

Have the unit professionally installed.

• Improper installation by an unqualified person may result in
water leak, electric shock, or fire.

Only use specified cables for wiring. Securely connect
each cable, and make sure that the cables are not
straining the terminals.

• Cables not connected securely and properly may generate
heat and cause fire.

Do not make any changes or modifications to the unit. In
case of problems, consult the dealer.

• Inadequate repairs may result in water leak, electric shock,
or file.

Only use Refrigerant R407C.

• The use of any other refrigerant or the introduction of air
into the unit circuit may damage the unit.

Have all electrical work performed by a licensed
electrician according to the local regulations and the
instructions given in this manual.
Secure a circuit designated exclusively to the unit.

• Improper installation or a lack of circuit capacity at the
power source presents a risk of electric shock or fire.

Be sure to carefully follow each step in this handbook
when installing the unit.

• Improper installation may result in water leak, electric
shock, or fire.

Securely attach the terminal cover (panel) on the unit.

• If installed improperly, dust and/or water may enter the unit
and fire or electric shock may result.

When relocating the air conditioner, consult the dealer or
a specialist.

• Improper installation may result in water leak, electric
shock, or fire.

After completing service work, check for refrigerant gas
leaks.

• If leaked refrigerant gas is exposed to a heart source, such
as fan heater, stove, and electric grill, noxious gases may
form.

Only use specified parts, and have the unit professionally
installed.

• Improper installation may result in water leak, electric
shock, or fire.

When installing the unit in a small room, safeguard
against hypoxia, which is caused by the leaked refrigerant
exceeding the threshold level.

• Consult the dealer for necessary measures to take.

When a gas leak is detected, provide adequate ventilation
to the room.

• If leaked refrigerant gas is exposed to a heat source,
noxious gases may form.

Do not try to defeat the safety features of the devices, and
do not change the settings.

• Defeating the safety features such as the ones on pressure
switch and temperature switch or using parts other than
those specified by Mitsubishi Electric may result in fire or
explosion.

Place the unit on a stable, level surface that will withstand
the weight of the unit to prevent the unit from toppling
over.

Take necessary safety measures against typhoons and
earthquakes to prevent the unit from toppling over.

Do not touch the fins on the heat exchanger with bare
hands: they are sharp and dangerous.

sBefore installing the unit, be sure to read all the “Safety Precautions” very carefully.
sThey provide very important information regarding safety. Be sure to take these precautions to ensure safety.

- 5 -

Caution

Precautions for Devices that Use R407C Refrigerant

Do not use existing refrigerant piping.

• The old refrigerant and refrigerator oil in the existing piping
contain a large amount of chlorine, which will deteriorate
the refrigerator oil in the new unit.

Use refrigerant pipes made of C1220 phosphorus
deoxidized copper categorized under H3000 (Copper and
Copper Alloy Seamless Pipes and Tubes), a standard set
by JIS.

• Keep inner and outer surfaces of the pipes clean and free
of contaminants, such as sulfur, oxides, dust/dirt, shaving
particles, oils, and moisture. Contaminants inside the
refrigerant piping will deteriorate the refrigerant oil.

Store the piping to be used during installation indoors,
and keep both ends of the piping sealed until immediately
before brazing. (Keep elbows and other joints wrapped in
plastic.)

• If dust, dirt, or water enters the refrigerant circuit,
deterioration of the oil or compressor problems may result.

Use a small amount of ester oil, ether oil, or alkylbenzene
to coat flares and flange connections.

• Refrigerator oil will deteriorate if it is mixed with a large
amount of mineral oil.

Be especially careful when managing tools.

• Exercise caution so that tools do not introduce dust, dirt,
and water into the refrigerant cycle.

Use liquid refrigerant to charge the circuit.

• Charging the unit with gas refrigerant will cause the
refrigerant in the cylinder to change its composition and will
lead to a drop in performance.

Only use R407C refrigerant.

• The use of other refrigerants containing chlorine (i.e. R22)
will deteriorate the refrigerant.

Do not use the following tools that have been used with
the existing refrigerators.

(Gauge manifold, charge hose, gas-leak detector, reverse­flow-check valve, refrigerant charge base, vacuum gauge,
and refrigerant recovery equipment.)

• If refrigerant and / or refrigerant oil left on these tools are

mixed in with R407 or if water is mixed with R407C
refrigerant, the refrigerant will deteriorate.

• Since R407C does not contain chlorine, gas-leak detectors

for conventional refrigerators will not work.

Do not use a charging cylinder.

• The use of charging cylinder will change the composition of

the refrigerant and lead to power loss.

Use a vacuum pump with a reverse-flow-check valve.

• If other types of valves are used, the vacuum pump oil will

flow back into the refrigerant circuit and deteriorate the
refrigerator oil.

- 6 -

Caution

Before Installing the Unit

Do not use the unit to preserve food, animals, plants, or
artifacts, or for other special purposes.

• The unit is not designed to provide adequate conditions to
preserve the quality of these items.

Use a closed circulating water circuit (which does not
release water in the air) as a heat source.

Do not install the unit in a place where there is a
possibility of flammable gas leak.

• Leaked gas accumulated around the unit may start a fire.

Do not use the unit in an unusual environment.

• Installing the unit in a place where a large amount of oil,
steam, or sulphurous gas is present may lead to a
remarkable drop in performance and/or damage to the unit.

Ground the unit.

• Do not connect the grounding on the unit to the grounding
terminals of gas pipes, water pipes, lightning rods, or
telephones. Improper grounding presents a risk of electric
shock.

Heat-Source Unit is only to be installed indoors (including
mechanical rooms). Make sure that the temperature
around the heat-source unit does not exceed 40˚CDB and
that it is out of direct sunlight.

• A sharp rise in the temperature inside the unit may damage
the unit.

When installing draining pipes, follow the instructions in
the manual and make sure that they properly drain water
as to prevent dew condensation.

• If not installed properly, water may leak and damage the
furnishings.

Make sure that the quality of circulating water meets the
standards set by Mitsubishi based on the Guidelines for
the Quality of Water for Refrigeration and Air Conditioning
established by the Japan Refrigeration and Air
Conditioning Industry Association.

• Using low-quality water may result in decreased
performance of the water-heat exchanger or corrosion.

Do not place the unit on or over things that should not get
wet.

• When humidity level exceeds 80% or when the drainage
system is clogged, indoor units may drip water. Installation
of a centralized drainage system for the heat-source unit
may also need to be considered to prevent water drips.

When installing the unit in hospitals, take necessary
measures against noise interference.

• High-frequency medical devices may interfere with the
normal operation of the air conditioning unit or vice versa.

• Water in an open circulating water circuit may become
contaminated when exposed to air and lead to a drop in
water-heat exchanger performance. It may also corrode the
exchanger.

Use breakers and fuses with proper current capacity. Do
not use large-capacity fuses, steel wire, or copper wire,
for they may damage the unit or cause fire.

For electrical wiring, use standard wires with proper
current capacity to prevent electric leak, overheating, and
fire.

Caution

Before Installing (Relocating) the Unit or Performing Electrical Work

Make sure the wires are not subject to tension.

• If the wires are too taut, they may generate heat and cause
fire.

Install a leak breaker at the power source to avoid the risk
of electric shock.

Do not spray water on air conditioners. Spraying the unit
presents a risk of electric shock.

Periodically check the platform on which the unit is placed
for damage to prevent the unit from toppling over.

- 7 -

Caution

Before Installing (Relocating) the Unit or Performing Electrical Work

Turn on the unit at least 12 hours before the test run, and
keep the unit on throughout the season.

• If the unit is turned off during the season, problems may
occur.

Do not turn off the power immediately after stopping the
unit.

• Wait for at least five minutes; otherwise, the unit may leak
water or experience other problems.

Do not touch refrigerant piping with bare hands during
and immediately after operation.

• Depending on the state of the refrigerant in the system,
refrigerator parts such as piping and compressor may
become very hot or cold and may subject the person to
frost bites or burning.

Do not operate the unit without panels and safety guards
in their proper places.

• They are provided to keep the users from injury from
accidentally touching rotating, high-temperature, or high­voltage parts.

Properly dispose of packing materials.

• Things such as nails and wood pieces may be included in
the package. Dispose of them properly to prevent injury.

• Plastic bags present a choking hazard to children. Tear up
the plastic bags before disposing of them to prevent
accidents.

Exercise caution when transporting products.

• Do not try to move equipments over 20kg (approx. 44 lbs.)
alone.

• Do not use the PP bands used on some packages for
transportation.

• Wear protective gloves to avoid injury caused by coming in
contact with the fins on the heat exchanger.

• When using suspension bolt to transport heat-source unit,
use four-point suspension. Three-point suspension does
not provide adequate stability and presents a risk of injury.

Caution

Before the Test Run

To prevent the risk of electric shock, do not operate
switches with wet hands.

Do not operate the unit without air filters.

• Dust particles in the air may clog the system.

- 8 -

Please Read Before Servicing the Unit

11

Check Before Servicing the Unit

[1] Find out the model type and refrigerant type of the unit to be serviced.

[2] Principal System Components

PUD-P250YMF-C

10HP(downward flow): PFD-P250VM-A(-H)
20HP(downward flow): PFD-P500VM-A(-H)

✻

'-H' in the indoor units indicates that the unit pipes come out of the top of the unit (50/60Hz, fit to order).

✻

PFD-type indoor units cannot be connected to outdoor units other than the ones specified above.

✻

PFD-type indoor units and other types of indoor units cannot coexist in the same refrigerant system.

} Outdoor Unit

} Indoor Unit

<10HP System>

<20HP System>

When using a PFD-P500VM-A as an indoor unit, connect 2 PUD-P250YMF-C outdoor units to each
indoor unit and operate with a built-in remote control for the indoor unit.

✻1: Bold line indicates refrigerant piping (gas/liquid). This system consists of 2 refrigerant circuits.
✻2: Indicates TB3-type transmission line that connects the indoor and outdoor units.

This system consists of 2 refrigerant circuits.

✻3: Indicates TB7-type transmission line that allows the unit to communicate with the controller.

When using a PFD-P250VM-A as an indoor unit, connect an outdoor unit PUD-P250YMF-C to
each indoor unit and operate with a built-in remote control for the indoor unit.

✻1: Bold line indicates refrigerant piping (gas/liquid). This system consists of one refrigerant circuit.
✻2: Indicates TB3-type transmission line that connects the indoor and outdoor units.

This system consists of 1 refrigerant circuit.

✻3: Indicates TB7-Type transmission line that allows the unit to communicate with the controller.

Outdoor Unit

G-50A

PUD-P250YMF-C

Indoor Unit

PFD-P250VM-A

TB7

TB3 ✻2✻3

✻1

12V DC

M-NET

PAC-SC50KUA

UP

POWER RATING

MODEL

WEIGHT
SERIAL No.

2.11kg

POWER SUPPLY UNIT

MITSUBISHI ELECTRIC CORPORATION

PAC-SC50KUA

Outdoor Unit

PUD-P250YMF-C

Indoor Unit

PFD-P500VM-A

TB7

TB3 ✻2

✻1

TB3

PUD-P250YMF-C

TB7

✻3

G-50A

12V DC

M-NET

PAC-SC50KUA

UP

POWER RATING

MODEL

WEIGHT
SERIAL No.

2.11kg

POWER SUPPLY UNIT

MITSUBISHI ELECTRIC CORPORATION

PAC-SC50KUA

- 9 -

[3] Check the symptoms of the unit requiring service.

Refer to this service manual for problems related to Freezer Cycle.

[4] Be sure to read Read Before Servicing at the beginning of this manual.

[5] Prepare necessary tools.

Do not use the same tools for units that use different types of refrigerant (especially gauze manifold and
charge hose). Doing so may cause problems. Use a vacuum pump with a reverse-flow check valve or use a
reverse flow check adapter.

[6] If the refrigerant circuit is opened (to repair gas leak etc.), the drier needs to be

replaced.

Only use the drier designed specifically for the unit. The use of other driers may result in malfunctions. Refer to
section 11 of this manual for information regarding how to change the drier.
✻ Replace the drier after completing refrigerant circuit repairs.

(If left exposed to air, the drier will absorb moisture. Replace the drier as quickly as possible after removing
the old one.)

[7] Preparing the connecting pipes: When relocating or replacing the unit, find out what

types of refrigerant is used for the unit.

Use refrigerant pipes made of C1220 phosphorus deoxidized copper categorized under H3000 (Copper and
Copper Alloy Seamless Pipes and Tubes), a standard set by JIS. Keep inner and outer surfaces of the pipes
clean and free of contaminants, such as sulfur, oxides, dust/dirt, shaving particles, oils, and moisture.
Contaminants inside the refrigerant piping will deteriorate the refrigerant oil.

[8] If there is a gas leak or if the remaining refrigerant is exposed to an open flame, a

noxious gas hydrofluoric acid may form. Provide adequate ventilation.

.

Caution

1. As soon as the old parts are removed, put in the new ones. Keep moisture from entering pipes while cooling.

2. Using refrigerant containing chlorine (such as R22) will result in the deterioration of oil in the new unit.

- 10 -

NotesUseTools

Identification of dedicated use with
R407C: Record refrigerant name
and put a brown belt on the upper
part of the cylinder.

Use a small amount of ester oil,
ether oil, or alkybenzene.

The ones with sight glass are useful.

Can also be used with R134a.

Gauge Manifold

Refrigerant Collector

Gas Leak Detector

Charge Hose

Refrigerant Cylinder

Application Oil

Evacuating, refrigerant
charging and operation check

Gas leak detection

Refrigerant collection

Refrigerant charging

Applied to flares and flanges

Attach a reverse-flow-check adaptor

Refrigerant Cylinder Intake Refrigerant charging

Replace the packing with the one
for R407C

Modifications to Be MadeUseTools

Vacuum Pump Vacuum drying

Vacuum Pump with a Check valve

Vacuum Gauze

Refrigerant Charging Meter

Welder and Nitrogen Cylinder

Pipe Cutter

Torque Wrench

Bender

Flare Tool Flaring pipes

Checking vacuum degree

Refrigerant charging

Welding pipes

Cutting pipes

Tightening flare nuts

Bending pipes

NotesUseTools

Must not be used with R407C-type
units

NotesUse (with R22)Tools

Charging Cylinder Refrigerant Charging

22

Necessary Tools and Materials

Prepare the following tools and materials. Some of the tools should be marked for use only with units that use
R407C refrigerant.

[1] List of Tools and Materials Necessary for Units that Use R407C (and adaptability of

tools that have been used with units that use R22)

(1) To be used with R407C Only (not to be used if used with R22)

(2) Tools that may be used for R407C if necessary modifications are made

(3) Tools that are used with R22 that can also be used with R407C

(4) Tools that must not be used for R407C

Tools for R407C must be handled with special care.

- 11 -

Do not use the piping that have been used for R22.

<Reason>

A large amount of chlorine residues from conventional refrigerator oil and refrigerant found inside the existing
piping deposit sludge in the new piping system.

<Caution>

1. When replacing the air conditioner, also replace the piping.

2. Use refrigerant pipes made of C1220 phosphorus deoxidized copper categorized under H3000 (Copper and
Copper Alloy Seamless Pipes and Tubes), a standard set by JIS. Keep inner and outer surfaces of the pipes
clean and free of contaminants, such as sulfur, oxides, dust/dirt, shaving particles, oils, and moisture.

3. Contaminants inside the refrigerant piping may deteriorate the refrigerant oil.

33

Piping Materials

NOOK

New Piping Existing Piping

Do not use the existing piping!

- 12 -

44

Storage of Piping Materials

[1] Storage Location

NONO

OKOK

NONO

OKOK

Store the pipes to be used indoors (i.e. warehouse).
Storing them outdoors may cause dirt, waste, or water to infiltrate.

[2] Pipe sealing before storage

Both ends of the pipes should be sealed until immediately before brazing.
Wrap elbows and T’s in plastic for storage.

✻ The new refrigerator oil is ten times more hygroscopic than conventional refrigerator oils (such as Suniso).

Water infiltration in the refrigerant circuit will deteriorate the oil or cause a compressor failure. Exercise more
caution when handling piping materials for R407C air conditioners than you would when handling piping
materials for conventional units.

- 13 -

55

Machining Pipes

Use a small amount of ester oil, ether oil, or alkylbenzene as refrigerator oil to coat flares and flange connections.

<Caution>

Use only the smallest possible amount of oil necessary.

Do not use oils other than ester oil, ether oil, or alkylbenzene.

- 14 -

<Items to be strictly observed>

1. Do not conduct piping work outdoors on a rainy day.

2. Apply non-oxide brazing.

3. Use brazing material (BCuP-3), which requires no flux when brazing copper pipe or brazing a copper pipe and
copper coupling.

4. If the installed refrigerant pipes are not immediately connected to the unit, braze and seal both ends of the
pipes.

<Rationale>

1. The new refrigerant oil is ten times more hygroscopic than conventional oils. Special care must be taken to
keep moisture out of the system.

2. Flux generally contains chlorine. A residual flux in the refrigerant circuit may deposit sludgy materials in the
pipes.

<Caution>

Because the residue found in commercially available antioxidants may have adverse effects on the unit, use
nitrogen when performing non-oxide brazing.

66

Brazing

Although there are no changes from the conventional method, special care must be taken to keep contaminants
(i.e. oxide scale, water, dirt etc.) from entering refrigerant circuit.

Example: Inside a brazed section

Brazed with materials other than non-oxide

brazing material

Brazed with non-oxide brazing material

- 15 -

NO NO

77

Testing Air Tightness

There are no changes from the conventional method. Note that a refrigerant leak detector for R22 will not work
for R407C.

<Items to be strictly observed>

1. Pressurize the equipment with nitrogen up to the design pressure, and then measure the equipment’s air-tight­ness, taking temperature variations into account.

2. When investigating locations of leaks using a refrigerant, be sure to use R407C.

3. Make sure that R407C is in a liquid state when charging the circuit.

<Rationale>

1. Use of oxygen to pressurize the equipment may cause an explosion.

2. If gas refrigerant is used, the composition of the remaining refrigerant in the cylinder will change and become
unusable.

<Caution>

A leak detector for R407C is commercially available, and it should be acquired.

Halide Torch R22 Leak Detector

- 16 -

[1] Vacuum pump with a check valve (See photo 1)

A vacuum pump with a check valve is required to prevent the vacuum pump oil from flowing back into the
refrigerant circuit when the power supply is cut off unexpectedly due to power outage.
A check valve may be added to a vacuum pump that is not equipped with one.

[2] Standard degree of vacuum for the vacuum pump

Use a pump that does not exceed 65Pa after 5 minutes of operation. Be sure to use a vacuum pump that has
been properly maintained and oiled with specified oil. If the vacuum pump is not properly maintained, desired
degree of vacuum may not be achieved.

[3] Necessary Accuracy of the Vacuum Gauge

Use a vacuum gauge that can measure 650Pa and in the increments/decrements of 130Pa. Do not use gauge
manifolds that cannot measure a vacuum of 650Pa. (Recommended vacuum gauze shown in Photograph 2
above)

[4] Vacuuming time

Evacuate the equipment for one hour after reaching 650Pa. (Moisture in the air will be removed by a thorough
evacuation.)
After evacuating, leave the equipment for one hour and make sure that degree of vacuum does not rise higher
than 130Pa. Refer to section 6 “Special Vacuuming Method” if it exceeds 130Pa.

[5] How to Stop the Vacuum Pump

In order to prevent a backflow of the vacuum pump oil, open the relief valve on the vacuum pump or loosen the
charge hose to draw in air before stopping the operation. The same operating procedure should be followed
when using a vacuum pump with a check valve.

[6] Special Vacuuming Method

Water infiltration or leakage is suspected when the degree of vacuum does not go below 650Pa after running
the vacuum pump for more than 3 hours. Check for leakage and water infiltration.
If water infiltration is the suspected cause, break vacuum with nitrogen. Then, pressurize nitrogen gas to

0.05MPa and try evacuating again. Repeat the procedure until the degree of vacuum goes below 650Pa or
until the pressure stops rising.
Be sure to use nitrogen to break vacuum. (The use of oxygen may cause an explosion)

Photograph 1 Photograph 2

Photograph 1 Recommended Vacuum Gauge : ROBINAIR 14010 Thermistor Vacuum Gauge

88

Vacuum Drying (Evacuating)

- 17 -

99

Charging the Circuit with Refrigerant

R407C must be in a liquid state when charging the circuit because it is a non-azeotropic refrigerant.

<Rationale>

1. R407C is a mixture of three refrigerants, each with a different evaporation temperature. If the equipment is
charged with R407C gas, only the refrigerant that evaporates most easily is charged, while the rest of the
refrigerants remain in the cylinder.

<Caution>

Do not use cylinders with a siphon upside-down.
When using a cylinder with a siphon, R407C is charged in a liquid state without the cylinder being turned upside­down. Check the label on the cylinder for information about the type of cylinder before the operation. (Cylinders
with siphons manufactured by Asahi Glass are shown on Page 18)

cylinder with a siphon

Cylinder color R407C-Brown

Cylinder

Cylinder

cylinder without a siphon

Use liquid refrigerant

Valve Valve

Liquid Liquid

- 18 -

Enlargement

Valve

Liquid

R407C Cylinder with siphon: Manufactured by Asahi Glass

.

Caution

The cylinders shown below are equipped with siphons.
When using this type of cylinders, place the cylinder
with the siphon facing up.

- 19 -

Drier

Direction of the flow Top to bottom

ø 9.52

Flare connection

ø 12.7

Flare connection

,

AA

Replacing the Drier

==

What to Do When Refrigerant Leaks

As with conventional air-conditioning units, refrigerant can be added to what remains in the circuit, for the unit is
equipped with a CS circuit (Circulating-Refrigerant-Composition-Detector) Refer to section X of this handbook for
more information.

✻ When using water-cooled heat-source unit, please note that CS circuit is only found on the inverter side, but not

on the constant-rate side.

1. Replace the drier when the refrigerant circuit is opened. Only use the drier specified for this unit. The use of any
other drier will cause malfunctions.

2. Install the drier as shown in the photograph below. Do not attach driers to a pipe;
doing so may cause problems.

3. Do not leave the refrigerant circuit open for longer than one hour after removing the old drier. The replacement of
the drier should be performed last when performing multiple jobs.

- 20 -

11

. Restrictions

11

System Restrictions and System Configuration

Each unit of the Split-Type Air Conditioners for Computer Rooms comes as a part of a system. For each unit to be
integrated into the system, the system requires a series of switch setting. Be sure to read the following to properly
configure the system.

[1] Switch Setting

(1) Types of Switches

✻ Inside indoor units, there is a control board for each refrigerant system.

Be sure to set the address for each of the control board.

2 Two or more identical addresses cannot coexist in the same system. If two or more of the same address

are used, the unit will not run properly.

(3) How to Set the Switches

1 Address Switch

(2) Notes on Switch Setting

1 Cut off the power supply before changing switch settings.

If the settings are changed while power is supplied to the unit, the change will not take effect, and it will
cause the unit to malfunction.

Type Outdoor Unit Indoor Unit

Address Switch rotary

™™

✻1

Power-Source Switch Connector 4-Pin connector CN40

™

Switches to Be Operated Cut off the power supply to

Outdoor Unit Outdoor unit

Indoor Unit Outdoor and Indoor Units

Unit Type

Setting

Range

Digits Setting Method

Factory

Setting

Indoor Unit 1-50 2

(the hundred's
digit is always
set to 0)

Outdoor Unit 51-100 2

00

00

(the hundred's
digit is always
set to 0)

· Use numbers between 1-50.

All the indoor units controlled by the same centralized

controller should be assigned sequential numbers
starting with 01.

· Only use odd numbers to set the top controller of the

indoor unit.

· To set the bottom controller of indoor units, add one to

the address of the top controller in the same unit. If
P250 and P500 systems coexist, Refer to P34.

· The address for the outdoor unit should equal the

address the of the indoor controller address in the
same refrigerant system plus 50.

- 21 -

(4) Example

Below is a typical setting of a system

Outdoor Units

Indoor UnitsController board

DC12V
Powe r
supply
line

Powe r

supply

unit

51

52

53

54

55

56

01

G-50A

02

03

04

05

06

0 1

57 07

59 09

Group 1

Group 2

Group 3

✻ There are two

controller boards
inside indoor units.
(for P500 type)

✻ There are one

controller board
inside indoor units.
(for P250 type)

SW12 SW11

Unit Address

10´s

Digits

Single

digits

Switch Setting

1 Set indoor unit address

using sequential numbers.
(P500 only)

2 To set the address for the

outdoor unit, add 50 to the
address for the indoor unit
to which the outdoor unit
is connected.

Diagram Comments

- 22 -

b) The control box cover consists of two parts (top and bottom parts). Each can be removed separately

by unscrewing two screws and pulling the cover down. Connectors and dipswitches on the main board
can be operated by removing only the top part. Only remove the bottom part when servicing power
supply lines and transmission lines.

a) Remove the service panel by unscrewing the 6 screws as shown in the picture on the right.

(2) Control Box and Location of Terminals

1 Outdoor Unit

Front Panel

22

Restrictions on Transmission Lines

[1] Electrical Wiring

(1) Attention

1 Follow ordinance of your governmental organization for technical standard related to electrical equipment,

wiring regulations, and guidance of each electric power company.

2 Wiring for control (hereinafter referred to as transmission line) shall be (5cm or more) apart from power

source wiring so that it is not influenced by electric noise from power source wiring.(Do not insert trans­mission line and power source wire in the same conduit.)

4 Give some allowance to wiring for electrical part box of indoor and outdoor units, because the box is

sometimes removed at the time of service work.

5 Never connect 380~415V(220~240V )power source to terminal block of transmission line.If

connected,electrical parts will be burnt out

6 Use 2-core shield cable for transmission line. If transmission lines of different systems are wired with the

same multiplecore cable, the resultant poor transmitting and receiving will cause erroneous operations.

NOOK

TB3

TB7

TB3

TB7

TB3

TB7

TB3

TB7

Multiple-core Cable

2-core Cable

2-core Cable

Indoor Unit

Indoor Unit

Outdoor Unit

Outdoor Unit

- 23 -

2 How to Use Conduit Mounting Plates

Conduit mounting plates (

ø 27, ø 33, ø 40) are packaged with the unit. Use an appropriate plate depend-

ing on the diameter of the wire used. Mount the plate as shown below.

3 How to Mount the Attachment Plate

When using either the left or front knock-out holes for both power-supply line and transmission line, screw
on an attachment plate with two screws (see below). Fix the power-supply line with the bottom clamp, and
fix the transmission line with the top clamp.

Front side

Controller

box

Transmission line

Power-Source line

Attachment plate

Use this hole when threading
the wire through the bottom hole

ø33 mounting plate

ø

40 mounting plate

ø27 mounting plate

ø27 mounting plate

ø33 mounting plate

ø

33 mounting plate

ø40

knockout hole

Tapping screw

Front Side of
the Panel

Use this hole when threading
the wire through the front hole.

- 24 -

Transmission line is a type of control line. When the source of noise is located adjacent to the unit, the use of
shield cable as well as moving the unit as far away from the noise source are recommended.

1 Transmission line (M-NET transmission line)

For multiple-refrigerant system

Length of transmission line

Facility type
(noise level measurement)

No. of cable 2-core cable

Diameter Over 1.25mm

2

Wiring specifications

All types of facilities

n/a

Shield cable
CVVS · CPEVS

System component

Maximum length: 200m
Maximum length of centralized control transmission line and Indoor/Outdoor
transmission line via indoor/outdoor units: 500m maximum

Total length of indoor/outdoor transmission line

Cable type

(4) Types of switch settings and setting methods

Whether a particular system requires switch settings depends on its components. Refer to the section
“(5) Examples” before conducting electrical work.
Keep the power turned off while setting the switches. If settings are changed while being powered, the
changed settings will not register, and the unit may malfunction.

Symbol

Outdoor unit OC

Indoor unit

✻ 10HP has only the main controller

Main/sub controllers ✻ IC

Turn off the power to

Outdoor unit

Indoor and outdoor units

Unit

2 Remote control wiring

MA remote controller ✻ 1

No. of cable 2-core cable

Diameter

0.3

~1.25mm

2

(0.75~1.25mm2)

✻ 2
✻ 3

Wiring specifications

CVV

Maximum length: 200 m

Total Length

✻ 1: “MA remote controller” includes MA remote controller, Simple MA controller, and wireless remote controller.
✻ 2: Cables with a diameter of 0.75mm

2

or smaller recommended for easier handling.

✻ 3: When connecting to simple remote controller terminal, use a cable with a diameter within the range shown in

the parenthesis.

Cable type

(3) Control Wiring

- 25 -

1 Address setting

This system requires address setting. The range of address varies depending on the type of unit.
Refer to “(5) Examples” for details.

3 Choosing the temperature detection spot by indoor unit (Factory Setting: SWC “Standard”)

When using the suction temperature sensor, set SWC to “Option.”

4 Setting the MA “Sub” controller

When using two remote controllers or running two indoor units as a group, one of the controllers must be
set to “Sub” controller.
✻ No more than two remote controllers can be connected to a group.

(Factory setting: “Main”)
Set the controller according to the following procedure. Refer also to the instructions manual supplied with
the MA remote controller.

Factory

setting

Indoor unit

Main/sub
controllers

✻ 1

Symbol Setting method

IC

OC

00

00

Address

setting range

01

~50

✻ 2

51

~100

✻ 2 ✻ 3

Unit

Outdoor Unit

✻ 1: 10HP only has the main controller.
✻ 2: Avoid using the same address as the ones used by the indoor/outdoor units in another refrigerant system; choose a different

one in the range specified above.

✻ 3: When setting the address to 100, set the switch to 50.

Assign a number to all indoor units, starting with 1 and using
sequential numbers. Use odd numbers for the top controller and
even numbers for the bottom controller of the indoor units. Use
odd numbers starting with 01 for 10HP system.

Add 50 to the address assigned to the indoor unit to which the
outdoor or heat-source unit is connected.

2 Setting the outdoor unit power-source switch connector (Factory setting: CN41 Connected)

Power supply switch unit

<When power-supply unit is not connected to the centralized control transmission line>

Replace the power source switch connector CN41 with CN40 on only one of the outdoor units

<When connecting the power-supply unit>

Use CN41 as it is.

System component

Multiple-refrigerant system

Remote controller bodyDip switches

1ON234

Screwdriver

Remove the cover on the remote controller

Set Dip Switch No.1 on the remote
controller to “OFF” (Main to Sub)

Insert a flat-head screwdriver in the
groove shown in the picture, and
move the screwdriver in the direction
shown in the arrow.

- 26 -

(5) Examples

1

System Using MA Remote Controller

(1) System with one indoor unit (10HP system)

Remarks Maximum Allowable Length

Control Wiring Diagram

<a. Indoor/Outdoor transmission line>

Maximum Length (above 1.25mm

2

)

L1 200m

1. Use power supply connector (CN41) on the outdoor
unit as is.

2. It is not necessary to ground the S terminal of
centralized control transmission terminal board (TB7)
on the outdoor unit.

3. The outdoor unit cannot be connected to indoor units
other than the PFD-type ones.

OC

TB3

TB7

EAB

ABS

51

IC

MA

TB5-1
ABS

01

TB15

12

A1 B2

L1

Use CN41 as is.

✻There is one indoor controller
board inside indoor unit.

- 27 -

Wiring and Address Setting

<a. Indoor/Outdoor Transmission Lines >

Connect A, B terminals of indoor/outdoor transmission line terminal board (TB3) on the outdoor unit and A, B
terminals of the Indoor/outdoor transmission terminal board (TB5). (Non-polar 2 wire)
✻ Only use shield line.

[Grounding the shield line]

Connect the earth terminal of the OC and S terminal of the IC terminal board (TB5).

<b. Switch Setting >

Set the address as follows.

MA
remote
controller

Sub Controller

Main ControllerMAMA

3

n/a

Main

Unit or Controller

Address

Setting Range

Steps

Factory
Setting

Setting Procedures

Indoor
Unit

Outdoor Unit

Main Unit IC

OC

1

2

Remarks

51 ~ 100

Sub controller

01 ~ 50 00

00

Set the address for the controller at the
top of the indoor unit. Start with "01"
then use sequential odd numbers
(i.e.01, 03, 05).

Add 50 to the address assigned to the
indoor unit within the same refrigerant
system.

Use dipswitch to set the controller as
sub controller.

-

1

System Using MA Remote Controller

(2) Unit with One Indoor Unit (20HP Systems)

Remarks Maximum Allowable Length

Control Wiring Diagram

1. Use sequential numbers to set indoor unit address.

2. Do not connect TB5s' of the indoor units that are
connected to different outdoor units with each other.

3. Replace CN41 with CN40 on only one outdoor unit.

4. Ground only one of the outdoor units' S terminal of
TB7 (centralized control transmission terminal).

5. The outdoor unit cannot be connected to indoor units
other than the PFD-type ones.

<a. Indoor/Outdoor transmission line>

Maximum Length (above 1.25mm

2

)

L1, L2 200m

<b. Transmission line for centralized control>

Maximum length via outdoor unit (over 1.25mm

2

)

L1 + L3 + L2 500m

NO

NO

OC

TB3

TB7

EAB

ABS

51

IC

MA

TB5-1
ABS

01

TB5-2
ABS

TB15

12

A1 B2

02

OC

TB3

TB7

EAB

ABS

52

L31

L1

L2

Use CN41 as is.

✻There are 2 indoor controller
boards inside indoor unit.

Replace CN41 with CN40.

Conect

- 28 -

Wiring and Address Setting

<a. Indoor/Outdoor Transmission Lines >

Connect A, B terminals of indoor/outdoor transmission line terminal board (TB3) on the outdoor unit and A, B
terminals of the Indoor/outdoor transmission terminal board (TB5). (Non-polar 2 wire)
✻Only use shield line.

[Grounding the shield line]

Connect the earth terminal of the OC and S terminal of the IC terminal board (TB5).

<b. Transmission Line for Centralized Control >

Connect A terminals of centralized control transmission line terminal board on each of the outdoor units with each
other.
Do the same with B terminals. Replace CN41 (power supply switch connector) with CN40 on only one OC.
✻Only use shield line.

[Grounding the shield line]

Connect S terminals of the TB7 of each of the outdoor units with each other.
Connect the S terminal of TB7 on the outdoor unit whose CN41 was replaced with CN40 to the earth terminal of
the electric box.

<c. Switch Setting >

Set the address as follows.

MA
remote
controller

Sub Controller

Main ControllerMAMA

3

n/a

Main

Unit or Controller

Address

Setting Range

Steps

Factory
Setting

Setting Procedures

Indoor
Unit

Outdoor Unit

Main Unit IC

OC

1

2

Remarks

51 ~ 100

Sub controller

01 ~ 49

00

00

Set the address for the controller at the
top of the indoor unit. Start with "01"
then use sequential odd numbers
(i.e.01, 03, 05).

Add 50 to the address assigned to the
indoor unit within the same refrigerant
system.

Use dipswitch to set the controller as
sub controller.

-

Sub Unit IC 02 ~ 50

Add 1 to the address assigned to the
main unit in the same room.

- 29 -