Carrier 38AU User Manual

38AU Air Cooled Condensing Units 60 Hz With PuronR(R---410A) Refrigerant S i z e s 1 6 --- 2 5

Installation, Start---Up and

Service Instructions

CONTENTS

SAFETY CONSIDERATIONS 2....................

INSTALLATION GUIDELINES 2..................

Replacement/Retrofit — R--22 to Puron 2...........

INSTALLATION 11 - 22.........................

Jobsite Survey 11...............................

Step 1 -- Plan for Unit Location 11.................

Step 2 -- Complete Pre--Installation Checks 11........

Step3–PrepareUnitMounting Support 12..........

Step4–RigandMount the Unit 12................

Step5–CompleteRefrigerantPipingConnections 12...

Step6–InstallAccessories 17....................

Step7–CompleteElectricalConnections 18.........

PRE-START-UP 23...............................

System Check 23...............................

Turn On Crankcase Heater 23.....................

Preliminary Charge 23...........................

START--UP 23 - 31..............................

Preliminary Checks 23...........................

Start Unit 24...................................

OPERATING SEQUENCE 32......................

Indoor (Supply) Fan 32..........................

Cooling, Unit Without Economizer 32..............

Cooling, Unit With Economizer 32.................

Heating 32....................................

ROUTINE SYSTEM MAINTENANCE 33............

Quarterly Inspection (and 30 days after initial start) 33...

Seasonal Maintenance 33........................

SERVICE 33 - 44................................

Compressor Oil 33..............................

Servicing Systems on Roofs with

Synthetic Materials 33...........................

Liquid Line Filter Drier 34.......................

Field Refrigerant Access Ports 34..................

Factory High--Flow Access Ports 34................

Comfort Alert Diagnostic Module 35...............

Compressor Protection 37........................

Crankcase Heater 37............................

Low--Pressure Switch 37.........................

High--Pressure Switch 37.........................

Outdoor Fans 37................................

Lubrication 37.................................

Coil Type Identification 42.......................

N O VAT I O N tCoil Cleaning and Maintenance 42.....

Repairing NOVATION Condenser Tube Leaks 42.....

Replacing NOVATION Condenser Coil 43...........

Routine Cleaning of Round-Tube Plate Fin

(RTPF) Coils 43................................

Fastener Torque Values 44........................

TROUBLESHOOTING 44 -- 45.....................

APPENDIX A Air Conditioner & Heat Pump with Puron

Quick Reference Guide 46.........................

APPENDIX B

Wiring Diagram List 46...........................

APPENDIX C

Low Ambient Option — Factory Installed 47..........

START--UP CHECKLIST 55 -- 56...................

—

Refrigeration System 33.........................

SAFETY CONSIDERATIONS

Improper installation, adjustment, alteration, service, maintenance, or use can cause explosion, fire, electrical shock or other conditions which may cause personal injury or property damage. Consult a qualified installer, service agency, or your distributor or branch for information or assistance. The qualified installer or agency must use factory-authorized kits or accessories when modifying this product. Refer to the individual instructions package

Follow all safety codes. Wear safety glasses and work gloves. Use quenching cloths for brazing operations and have a fire extinguisher available. Read these instructions thoroughly and follow all warnings or cautions attached to the unit. Consult local building codes and appropriate national electrical codes (in USA, ANSI/NFPA70, National Electrical Code (NEC); in Canada, CSA C22.1) for special requirements.

38AU

It is important to recognize safety information. This is the safety--alert symbol

unit and in instructions or manuals, be alert to the potential for personal injury.

Understand the signal words DANGER, WARNING, CAUTION, and NOTE. These words are used with the safety-alert symbol. DANGER identifies the most serious hazards which will result in severe personal injury or death. WARNING signifies hazards which could result in personal injury or death. CAUTION is used to identify unsafe practices, which may result in minor personal injury or product and property damage. NOTE is used to highlight suggestions which will result in enhanced installation, reliability, or operation.

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could cause in personal injury or death.

Before performing service or maintenance operations on unit, always turn off main power switch to unit and install lockout tag. Unit may have more than one power switch.

UNIT OPERATION AND SAFETY HAZARD

Failure to follow this warning could cause in personal injury,death and/or equipment damage.

Puron higher pressures than standard R--22 systems. Do not use R--22 service equipment or components on Puron refrigerant equipment.

(R--410A) refrigerant systems operate at

. When you see this symbol on the

WARNING

PERSONAL INJURY AND ENVIRONMENTAL HAZARD

Failure to follow this warning could cause in personal injury or death.

Relieve pressure and recover all refrigerant before system repair or final unit disposal.

Wear safety glasses and gloves when handling refrigerants. Keep torches and other ignition sources away from refrigerants and oils.

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care and wear appropriate protective clothing, safety glasses and gloves when handling parts and servicing 38AU units.

INSTALLATION GUIDELINE

Replacement/Retrofit — R--22 to Puron

Replacement/retrofit installations require change-out of outdoor unit, metering device, and filter driers. Change-out of indoor coil (evaporator) and interconnecting tubing is recommended.

Existing evaporator coil – If the existing evaporator coil may be re-used, check with the coil manufacturer to verify the coil construction is suitable for operation with the higher pressures of Puron the existing TXV valve is compatible with R-410A, replace if necessary. The minimum factory test pressure rating must be 250 psig (1725 kPa). Existing coil will need to be purged with Nitrogen to remove as much mineral oil as possible to eliminate cross contamination of oils.

Acid test – If the existing system is being replaced because of a compressor electrical failure, assume acid is in system. If system is being replaced for any other reason, use an approved acid test kit to determine acid level. If even low levels of acid are detected, install a 100 percent activated alumina suction-line filter drier in addition to the replacement liquid-line filter drier. Remove the suction line filter drier as soon as possible, with a maximum of 72 hr of operation. Recommendation: Install a ball valve in the liquid line at the filter drier location when installing a suction filter in the suction line.

Existing refrigeration piping – Reuse of existing refrigerant piping involves three issues: quality (strength) of existing tubing, cleanliness and tube size. Inspect all tube segments and joints for signs of damage, corrosion or poor brazing. Flush the interconnecting piping system with dry Nitrogen to eliminate as much trace of mineral oil as possible.

(R-410A). Also determine if

Same tube sizes are capable of handling higher flowrates (expressed as tons of cooling capacity) with Puron refrigerant compared to R--22 at constant pressure drops. For example, a higher tons with Puron drop). A 1 tons with Puron than with R--22 (at 2_F pressure drop). Refrigeration lines selected for R--22 use are typically oversized for Puron applications. Carefully check the existing suction line size against the table for maximum size (see Table 7); replace vertical riser segments if necessary. Check existing liquid line size against sizing data in Table 5 or 6; replace with smaller lines when feasible.

Installation –

1. Remove the existing evaporator coil or fan coil and install the replacement coil when appropriate.

2. Drain oil from low points and traps in suction line tubing (and hot gas bypass tubing if appropriate) and evaporator if they were not replaced. Removing oil from evaporator coil may require purging of the tubing with dry nitrogen.

3. Unless indoor unit is equipped with a Puron® approved metering device, change the metering device to a thermal expansion valve (TXV) designed for Puron

4. Remove the existing outdoor unit. Install the new outdoor unit according to these installation instructions.

/2--inch OD liquid line is rated at 33%

/8--inch OD suction line is rated at 53% higher

(R-410A).

than with R--22 (at 5_F pressure

5. Install a new field-supplied liquid-line filter drier at the indoor coil just upstream of the TXV or fix orifice metering device.

6. If a suction line filter drier is also to be installed, install suction line drier downstream of suction line service valve at condensing unit.

CAUTION

UNIT DAMAGE HAZARD

Failure to follow this caution may result in equipment damage or improper operation.

Never install suction--line filter drier in the liquid--line of a Puron

7. If required, install a 100% activated alumina suction line filter drier at the outdoor unit.

8. Evacuate and charge the system according to the instructions in this installation manual.

9. Operate the system for 10 hr. Monitor the pressure drop across the suction line filter drier. If pressure drop exceeds 3 psig (21kPa), replace suction-line and liquid-line filter driers. Be sure to purge system with dry nitrogen and evacuate when replacing filter driers. Continue to monitor the pressure drop across suction-line filter drier. Repeat filter changes is necessary. Never leave suction-line filter drier in system longer than 72 hr (actual time).

system.

38AU

C10942

UNIT

Standard

Weight

Corner

Center of Gravity

Unit

Height

lbs. kg. lbs. kg. lbs. kg. lbs. kg. lbs. kg. X Y Z H

38AUZ*16

(MCHX)

38AUD*16

(MCHX)

38AUZ*16

(RTPF)

38AUD*16

(RTPF)

LEGEND: MCXH = Novation™ coil

633 288 220 100 134 61 135 61 144 65.5

731 332 237 107 172 78 135 61 186 84

RTPF = Round Tube/Plate Fin coil

[965.2]

[482.6]

[381]

[431.8]

503/

[1279.2]

503/

[1279.2]

503/

[1279.2]

503/

[1279.2]

Fig. 1 -- 38AU**16 Unit Dimensions

UNIT

Standard

Weight

Corner

lbs. kg. lbs. kg. lbs. kg. lbs. kg. lbs. kg. X Y Z H

38AUZ*25

(RTPF)

38AUD*25

(RTPF)

LEGEND: RTPF = Round Tube/Plate Fin coil

978 444 360 163 188 85 147 67 283 128

Corner

Fig. 2 -- 38AU**25 Unit Dimensions

Center of Gravity

[965.2]

[584.2]

[431.8]

Unit

Height

503/

[1279.2]

503/

[1279.2]

38AU

C10943

Table 1A — Physical Data — 38AUZ*16-25 Units — 60 Hz English

UNIT SIZE 38AU Z*16 Z*25

NOMINAL CAPACITY (tons) 15 20

OPERATING WEIGHTS (lb)

NOVATION™ Coil (Al Tube) 633 ---

Round Tube/Plate Fin Coil (Cu/Al) 731 900

REFRIGERANT TYPE

NOVATION Operating Charge, Typical (lb)

NOVATION Shipping Charge (lb) 12.2 ---

RTPF Operating Charge, Typical (lb)

RTPF Shipping Charge (lb) 32.0 28.0

COMPRESSOR

Qty...Type 2...Scroll 2...Scroll

38AU

Oil Charge (oz) 60 110

CONDENSER FANS

Qty...Rpm 3...1100 4...1100

Motor Hp

Diameter 22 22

Nominal Airflow (Cfm Total) 9,000 12,000

Watts (Total) 970 1150

RTPF CONDENSER COIL

Material (Tube/Fin) Cu / Al Cu / Al

Coil Type

Rows/Fins per inch (FPI) 2/17 2/17

Face Area (sq ft total) 47.0 50.0

NOVATION CONDENSER COIL

Material (Tube/Fin) Al / Al ---

Coil Type Novation ---

Rows/Fins per inch (FPI) 1/17 ---

Face Area (sq ft total) 50.0 ---

CONTROLS

Pressurestat Settings (psig)

High Cutout 630 ± 10

Cut-in 505 ± 20

Low Cutout 54 ± 3

Cut-in 117 ± 5

PIPING CONNECTIONS (in. ODS)

Qty...Suction 1...13/

Qty...Liquid 1...5/

LEGEND

RTPF — Round Tube/Plate Fin ODS — Outside Diameter Sweat (socket)

‡

Unit is factory-suppl ied with partial charge on ly.

†

Typical operating ch arge with 25 ft of interconnecting piping.

‡

†

24.6 ---

43.0 38.0

/8--- i n R T P F

R-410A

/8--- i n R T P F

1...15/

1...5/

Table 1B — Physical Data — 38AUZ*16-25 Units — 60 Hz SI

UNIT SIZE 38AU Z*16 Z*25

NOMINAL CAPACITY (kW) 52.7 70.3

OPERATING WEIGHT (kg)

NOVATION™ Coil (Al Tube) 288 ---

Round Tube/Plate Fin Coil (Cu/Al) 332 409

REFRIGERANT TYPE

NOVATION Operating Charge, Typical (kg)

NOVATION Shipping Charge (kg) 5.4 ---

RTPF Operating Charge, Typical (kg)

RTPF Shipping Charge (kg) 14.5 12.7

COMPRESSOR Scroll

Qty...Type 2...Scroll 2...Scroll

Oil Charge (L) 1.7 3.2

CONDENSER FANS

Qty...r/s 3...18 4...18

Motor Hp NEMA

Diameter (mm) 560 560

Nominal Airflow (L/s) 4248 5663

Watts (Total) 970 1150

RTPF CONDENSER COIL (Qty)

Material (Tube/Fin) Cu / Al Cu / Al

Coil Type

Rows/Fins per Meter (Fins/m) 1...670 2...670

Face Area (sq m total) 4.4 4.6

NOVATION CONDENSER COIL

Material (Tube/Fin) Al / Al ---

Coil Type Novation ---

Rows/Fins per Meter (Fins/m) 1...670 ---

Face Area (sq m total) 4.6 ---

CONTROLS

Pressurestat Settings (kPa)

High Cutout 4347 ± 70

Cut-in 3482 ±138

Low Cutout 372 ± 21

Cut-in 807 ± 34

PIPING CONNECTIONS (mm ODS)

Qty...Suction 1...34.9 1...38.7

Qty...Liquid 1...13.3 1...13.3

LEGEND

RTPF — Round Tube/Plate Fin NEMA — National Electrical Manufacturers Association ODS — Outside Diameter Sweat (socket)

‡

Unit is factory-suppl ied with partial charge on ly.

†

Typical operating charge with 7.62 m of interconnecting piping.

‡

†

11.1 ---

19.5 17.2

/8--- i n R T P F

R-410A

/8--- i n R T P F

38AU

Table 2A — Physical Data — 38AUD*16-25 Units — 60 Hz English

UNIT SIZE 38AU D*16 D*25

NOMINAL CAPACITY (tons) 15 20

OPERATING WEIGHTS (lb)

NOVATION™ Coil (Al Tube) 633 ---

Round Tube/Plate Fin Coil (Cu/Al) 731 900

REFRIGERANT TYPE

NOVATION Operating Charge A/B, Typical (lb)

NOVATION Shipping Charge A/B (lb) 6.0 / 6.0 ---

RTPF Opera ting Charge A/B, Typical (lb)

RTPF Shipping Charge A/B (lb) 16.0 / 16.0 14.0 / 14.0

COMPRESSOR

Qty...Type 2...Scroll 2...Scroll

38AU

Oil Charge A/B (oz) 60 / 60 110 / 110

CONDENSER FANS

Qty...Rpm 3...1100 4...1100

Motor Hp

Diameter 22 22

Nominal Airflow (Cfm Total) 9,000 12,000

Watts (Total) 970 1150

RTPF CONDENSER COIL

Material (Tube/Fin) Cu / Al Cu / Al

Coil Type

Face Area (sq ft total) 47 50

Rows/Fins per inch (FPI) 2/17 2/17

NOVATION CONDENSER COIL

Material (Tube/Fin) Al / Al ---

Coil Type Novation ---

Face Area (sq ft total) 50 ---

Rows/Fins per inch (FPI) 1/17 ---

CONTROLS

Pressurestat Settings (psig)

High Cutout 630 ± 10

Cut-in 505 ± 20

Low Cutout 54 ± 3

Cut-in 117 ± 5

PIPING CONNECTIONS (in. ODS)

Qty...Suction 2...13/

Qty...Liquid 2...1/

LEGEND

RTPF — Round Tube/Plate Fin ODS — Outside Diameter Sweat (socket)

‡

Unit is factory-suppl ied with partial charge on ly.

†

Typical operating ch arge with 25 ft of interconnecting piping.

‡

†

12.0 / 12.0 ---

†

22.0 / 22.0 19.0 / 19.0

/8--- i n R T P F

R-410A

/8--- i n R T P F

2...13/

2...1/

Table 2B — Physical Data — 38AUD*16-25 Units — 60 Hz SI

UNIT SIZE 38AU D*16 D*25

NOMINAL CAPACITY (kW) 52.7 70.3

OPERATING WEIGHT (kg)

NOVATION™ Coil (Al Tube) 288 ---

Round Tube/Plate Fin Coil (Cu/Al) 332 409

REFRIGERANT TYPE

NOVATION Operating Charge A/B, Typical (kg)

NOVATION Shipping Charge A/B (kg) 2.7 / 2.7 ---

RTPF Operating Charge A/B, Typical (kg)

RTPF Shipping Charge A/B (kg) 7.3 / 7.3 6.8 / 6.8

COMPRESSOR

Qty...Type 2...Scroll 2...Scroll

Oil Charge A/B (L) 1.7 / 1.7 3.2 / 3.2

CONDENSER FANS

Qty...r/s 3...18 4...18

Motor Hp NEMA

Diameter (mm) 560 560

Nominal Airflow (L/s) 4248 5663

Watts (Total) 970 1150

RTPF CONDENSER COIL (Qty)

Material (Tube/Fin) Cu / Al Cu / Al

Coil Type

Rows/Fins per Meter (Fins/m) 1...670 2...670

Face Area (sq m total) 4.4 4.6

NOVATION CONDENSER COIL

Material (Tube/Fin) Al / Al ---

Coil Type Novation ---

Rows/Fins per Meter (Fins/m) 1...670 ---

Face Area (sq m total) 4.6 ---

CONTROLS

Pressurestat Settings (kPa)

High Cutout 4347 ± 70 4347 ± 70

Cut-in 3482 ±138 3482 ±138

Low Cutout 372 ± 21 372 ± 21

Cut-in 807 ± 34 807 ± 34

PIPING CONNECTIONS (mm ODS)

Qty...Suction 2...34.9 2...34.9

Qty...Liquid 2...12.7 2...12.7

LEGEND

RTPF — Round Tube/Plate Fin NEMA — National Electrical Manufacturers Association ODS — Outside Diameter Sweat (socket)

‡

Unit is factory-suppl ied with partial charge on ly.

†

Typical operating charge with 7.62 m of interconnecting piping.

‡

†

R-410A R-410A

5.4 / 5.4 ---

10.0 / 10.0 8.6 / 8.6

/8--- i n R T P F

38AU

1 2 3 4 5 6 7 8 9 101112131415161718

38AUZA25A0G6A0A0A0

Model Type

38AU= Carrier Condensing Unit

Puron

R--- 410A Refrigerant

Typ e o f C oi l

Z = Single Circuit, A/C Scroll Compressor

D = Dual Circuit, A/C Scroll Compressor

Refrigerant Options

A = None B = Low Ambient

Nominal Tonnage

16 = 15 Tons

25 = 20 Tons

Not Used

A = Not Used

38AU

Not Used

0 = Not Used

Packaging

0=Standard

1=LTL

Electrical Options

A=None

C = Non-Fused Disconnect

Service Options

0=None 1 = Un-powered Convenience Outlet1= 2 = Powered Convenience Outlet

Not Used

A=PlaceHolder

Base Unit Controls

0 = Electro-Mechanical Controls

Design Rev

A = Initial Release

Voltage

1 = 575/3/60 5 = 208 / 230/3/60 6 = 460/3/60

POSITION NUMBER TYPICAL

Coil Options

NOVATION™ (Size 16 only) G= Al/Al K = E-Coat Al/Al T = Al/Al with Hail Guard W= E-Coat Al/Al with Hail Guard

RTPF (Sizes 16 & 25) A= Cu/Al B = Precoat (Cu/Al) C = E-Coat (Cu/Al) M= Cu/Al with Hail Guard N = Precoat (Cu/Al) with Hail Guard P = E-Coat (Cu/Al) with Hail Guard

Fig. 3 -- Model Number Nomenclature

12345678910 0510U12345

POSITION

1 – 2 3 – 4

6 – 10

Week of manufacture (fiscal calendar)

Year of manufacture ("10" = 2010)

Manufacturing location (U = Monterrey, Mexico)

DESIGNATES

Sequence number

Fig. 4 -- Serial Number Nomenclature

C10944

C101041

Matching 38AU Model To Evaporator Coil

The Model 38AUZ is a single-circuit unit design, requiring one set of refrigeration piping. This model can be connected to an evaporator coil with one circuit or with two circuits (by manifolding the evaporator connections into a single piping system).

The Model 38AUD is a dual-circuit unit design that requires two sets of refrigeration piping between the outdoor unit and the evaporator coil (or coils). This model can only be connected to an evaporator coil that has two refrigeration circuits (or to two separate evaporator coils). The Model 38AUD CANNOT be connected to a single-circuit evaporator coil. The Model 38AUD CANNOT be field-converted to a single-circuit design.

Table 3 – Evaporator Coil Connections

Evaluate the path and required line length for interconnecting refrigeration piping, including suction riser requirements (outdoor unit above indoor unit), liquid line lift (outdoor unit below indoor unit) and hot gas bypass line. Relocate sections to minimize the length of interconnecting tubing.

DO NOT BURY REFRIGERATION LINES.

Although unit is weatherproof, avoid locations that permit water from higher level runoff and overhangs to fall onto the unit.

REAR: Min 18” (457 mm) requried for service

RIGHT: Min 18” (457 mm) requried for service

Evaporator Coil has Connect to Model Notes

Single Circuit 38AUZ ONLY

Two Circuits

38AUZ

38AUD Use two separate

Manifold evaporator circuits into single piping system

piping systems

Before unpacking this new 38AU model, compare the evaporator coil design to the 38AU model.

.INSTALLATION

Jobsite Survey

Complete the following checks before installation.

1. Consult local building codes and the NEC (National Electrical Code) ANSI/NFPA 70 for special installation requirements.

2. Determine unit location (from project plans) or select unit location.

3. Check for possible overhead obstructions which may interfere with unit lifting or rigging.

Step 1 — Plan for Unit Location

Select a location for the unit and its support system (pad, rails or other) that provides for the minimum clearances required for safety. This includes the clearance to combustible surfaces, unit performance and service access below, around and above unit as specified in unit drawings. See Fig. 5.

NOTE: Consider also the effect of adjacent units on airflow performance and control box safety clearance.

Do not install the outdoor unit in an area where fresh air supply to the outdoor coil may be restricted or when recirculation from the condenser fan discharge is possible. Do not locate the unit in a well or next to high walls.

LEFT: Min 18” (457 mm) requried for service

Note: Observe requirements for 39” (914 mm) operating clearance on either Left or Rear coil opening.

FRONT: 42” (1067 mm)

C10201

Fig. 5 -- Service Clearance Dimensional Drawing

Step 2 — Complete Pre-Installation Checks

Check Unit Electrical Characteristics: Confirm before

installation of unit that voltage, amperage and circuit protection requirements listed on unit data plate agree with power supply provided.

Un--crate Unit: Remove unit packaging except for the top skid assembly, which should be left in place until after the unit is rigged into its final location.

Inspect Shipment: File a claim with shipping company if the shipment is damaged or incomplete.

Consider System Requirements:

S Consult local building codes and National Electrical

Code (NEC, U.S.A.) for special installation requirements.

S Allow sufficient space for airflow clearance, wiring,

refrigerant piping, and servicing unit. See Fig.1 and Fig. 2 for unit dimensions and weight distribution data.

S Locate the unit so that the outdoor coil (condenser)

airflow is unrestricted on all sides and above.

S The unit may be mounted on a level pad directly on the

base channels or mounted on raised pads at support points. See Tables 1A through 2B for unit operating weights. See Fig. 1 and Fig. 2 for weight distribution based on recommended support points.

NOTE: If vibration isolators are required for a particular installation, use the data in Fig. 1 and Fig. 2 to make the proper selection.

38AU

Step 3 — Prepare Unit Mounting Support

Slab Mount —

Provide a level concrete slab that extends a minimum of 6 in. (150 mm) beyond unit cabinet. Install a gravel apron in front of condenser coil air inlet to prevent grass and foliage from obstructing airflow.

Step 4 — Rig and Mount the Unit

UNIT DAMAGE HAZARD

Failure to follow this caution may result in equipment damage.

All panels must be in place when rigging. Unit is not designed for handling by fork truck.

Rigging: These units are designed for overhead rigging.

38AU

Refer to the rigging label for preferred rigging method. Spreader bars are not required if top crating is left on the unit. All panels must be in place when rigging. As further protection for coil faces, plywood sheets may be placed against the sides of the unit, behind cables. Run cables to a central suspension point so that the angle from the horizontal is not less than 45 degrees. Raise and set the unit down carefully.

If it is necessary to roll the unit into position, mount the unit on longitudinal rails, using a minimum of 3 rollers. Apply force to the rails, not the unit. If the unit is to be skidded into position, place it on a large pad and drag it by the pad. Do not apply any force to the unit.

Raise from above to lift the unit from the rails or pad when unit is in its final position.

After the unit is in position, remove all shipping materials and top crating.

CAUTION

Step 5 — Complete Refrigerant Piping Connections

IMPORTANT: Do not bury refrigerant piping

underground.

IMPORTANT: A refrigerant receiver is not provided with the unit. Do not install a receiver.

Provide Safety Relief —

If local codes dictate an additional safety relief device, purchase locally and install locally. Installation will require the recovery of the factory shipping charge before the factory tubing can be cut and the supplemental relief device is installed.

Model 38AUD has two separate refrigeration systems. If required, each circuit will require a field-supplied/installed supplemental relief device.

Table 4 – Equivalent Lengths for Common Fittings (ft)

Nominal

Tube OD

11/

13/

15/

21/

Nominal

Tube OD

11/

13/

15/

21/

90° Std 90° Lrad 90° Street 45° Std 45° Street

1.3 0.8 2.2 0.6 1

1.4 0.9 2.3 0.7 1.1

1.6 1 2.5 0.8 1.3

1.8 1.2 2.9 0.9 1.5

2 1.4 3.2 0.9 1.6

2.6 1.7 4.1 1.3 2.1

3.3 2.3 5.6 1.7 3

4 2.6 6.3 2.1 3.4

5 3.3 8.2 2.6 4.5

Branch

Flow

2.6 0.8 1.1 1.3

2.7 0.9 1.2 1.4

3.5 1.2 1.7 1.8

10 3.3 4.7 5

No Reduct Reduce 25% Reduce 50%

3 1 1.4 1.6

4 1.4 1.9 2

5 1.7 2.3 2.6

7 2.3 3.1 3.3

8 2.6 3.7 4

Elbows

Tees

Straight-Thru

Check 38AU Model with Evaporator Coil Connections —

Confirm before installation of unit that the evaporator coil connections are consistent with this 38AU model. See Table 3 on page 11.

Determine Refrigerant Line Sizes —

Select the recommended line sizes for 38AUZ and 38AUD unit from the appropriate tables.

Determine the linear length of interconnecting piping required between the outdoor unit and indoor unit (evaporator). Consider and identify also the arrangement of the tubing path (quantity and type of elbows in both lines), liquid line solenoid size, filter drier and any other refrigeration specialties located in the liquid line. Refer to the indoor unit installation instructions for additional details on refrigeration specialties devices.

Determine equivalent line length adjustments for path and components and add to linear line lengths. See Table 4, Equivalent Lengths for Common Fittings, for usual fitting types. Also identify adjustments for refrigeration specialties. Refer to Part 3 of the Carrier System Design Manual for additional data and information on equivalent lengths.

NOTE: Equivalent line lengths will vary based on tube diameter. Calculate equivalent line length for each pipe by adding equivalent length adjustments to linear lengths for each pipe.

Enter the appropriate table to select the recommended line sizes.

Model: Line Sizes Table Quantity of Line Sets

38AUZ 5 1

38AUD 6 2

Liquid Lift —

A liquid lift condition exists when the outdoor unit is located below the indoor (evaporator) unit and liquid flows vertically up in a portion of the liquid line. The vertical column of liquid reduces the available state point subcooling at the evaporator coil’s thermal expansion valve. This effect reduces the length of liquid lift (feet of elevation) that a liquid line size can accommodate. Longer linear tube lengths will also reduce the amount of liquid lift possible.

Check Tables 5 (38AUZ) and 6 (38AUD) for maximum liquid lift capabilities for line sizes. Reselect the liquid

Table 5 – 38AUZ 16-25 Piping Recommendations (Single-Circuit Unit)

R-410A Equivalent Length

Ft 0-38 38-75 75-113 113-150 150-188

m 0-12 12-23 23-34 34-46 46-57

Linear Length

Ft 0-25 25-50 50-75 75-100 100-125

Model

38AUZ*16 Liquid Line

38AUZ*25 Liquid Line

Legend:

Equivalent Length

Linear Length Typical linear tubing length, (50% added to l inear to define E quivalent Length for this table)

Liquid Line Tubing size, inches OD.

Max Lift Maximum liquid lift (indoor unit ABOVE outdoor unit only), at maximum permitted liquid line pressure drop —

Suction Line Tube size, inches OD

Charge Charge Quantity, lbs. Calculated for both liquid line sizes (where applicable), but only with larger suction line size

NOTE: For applications with equivalent length greater than 188 ft (57 m) and/0r linear length greater than 125 ft (38 m),

m 0-8 8-15 15-23 23-30 30-38

Max Lift 25 50 75 100 125

Suction Line 1-1/

Charge (lbs)

Novation 24.3 27.5 30.6 33.7 37.8

RTPF 42.7 45.9 49.0 52.1 56.2

Max Lift 25 50 71 77 63

Suction Line 1-1/81-3/81-3/

Charge (lbs) 37.8 40.8 44.6 47.8 51.1

Equivalent tubing length, including effects of refrigeration specialties devices

S Linear Length Less than 75 ft (23 m): Minimum 2.0° F subcooling entering TXV S Linear Length Greater than 75 ft (23m): Minimum 0.5° F subcooling entering TXV

(where applicable)

contact your local Carrier representative.

1-3/

line tube size if necessary. If maximum available tube size cannot provide the required lift distance on this installation, relocate the outdoor unit to reduce the equivalent line length or the lift requirement.

Suction Riser —

A suction riser condition exists when the outdoor unit is located above the indoor (evaporator) unit and suction vapor must flow vertically up to return to the compressor. Oil return is a concern when the suction tube size is too large to produce the minimum refrigerant velocity to ensure oil return at minimum load conditions.

Check Table 7 for maximum suction tube size for 38AU units at minimum load conditions. Consider suction speed riser (reduced tube size for vertical segment only) or double suction riser arrangement if the recommended suction tube size does not provide necessary minimum flowrates for this riser.

1-3/

1-3/81-5/81-5/

1-3/

1-3/81-5/

1-5/

38AU

Table 6 – 38AUD 16-25 Piping Recommendations (Two-Circuit Unit)

NOTE: 38AUD requires TWO sets of refrigeration piping

R-410A Equivalent Length

Ft 0-38 38-75 75-113 113-150 150-188

m 0-12 12-23 23-34 34-46 46-57

Linear Length

Ft 0-25 25-50 50-75 75-100 100-125

Model

38AUD*16 Liquid Line

38AUD*25 Liquid Line

38AU

Legend:

Equivalent Length

Linear Length Typical linear tubing length (50% added to linear to define Equivalent L ength for this table)

Liquid Line Tubing size, inches OD.

Max Lift Maximum liquid lift (indoor unit ABOVE outdoor unit only), at maximum permitted liquid line pressure drop —

Suction Line Tube size, inches OD

Charge Charge Quantity, lbs. Calculated for both liquid line sizes (where applicable), but only with larger suction line size

NOTE: For applications with equivalent length greater than 188 ft (57 m) and/0r linear length greater than 125 ft (38 m),

m 0-8 8-15 15-23 23-30 30-38

Max Lift 25 50 75 100 125

Suction Line

Charge ea. (lbs)

Novation 11.7 13.8 15.7 17.6 19.6

RTPF 21.7 23.8 25.7 27.6 29.6

Max Lift 25 50 54 75 60 99 46 95

Suction Line 11/

Charge (lbs) 1219.3

Equivalent tubing length, including effects of refrigeration specialties devices

S Linear Length Less than 75 ft (23 m): Minimum 2.0° F subcooling entering TXV S Linear Length Greater than 75 ft (23m): Minimum 0.5° F subcooling entering TXV

(where applicable)

contact your local Bryant representative.

18.3

11/

21.0

20.3

11/

23.0

22.0

26.0

25.0

11/

25.9

24.9

13/813/

29.7

28.7

11/

28.0

27.0

32.7

31.7

Ta bl e 7 – 38AU Maximum Suction Pipe Size

Model: Unit Size Maximum Tube Size

38AUZ

38AUD

16 15/

25 15/

16 15/

25 15/

Vertical Separation (outdoor unit above indoor unit) –

Vertical elevation difference of 200 ft (60 m) is permitted when the outdoor unit (38AUZ or 38AUD) is located above the indoor unit.

Insulate Suction Lines —

Apply closed-cell tubular insulation to all suction lines between evaporator coil connection and 38AU unit’s suction service valve.

Hot Gas Bypass —

Hot gas bypass, if used, should be introduced before the evaporator. (A bypass route that also bypasses the evaporator circuit may lead to oil trapping in the evaporator circuit during low load conditions and then to oil slugging as evaporator load increases.) Model 38AU units do not include a hot gas stub connection; a tee must be field-supplied and

installed in the compressor discharge line. Run a

/2-in OD line between outdoor unit and evaporator coil inlet. Install an Auxiliary Side Connector at the evaporator between TXV and distributor (follow instructions for the side connector part). Insulate the hot gas line.

38AUD: Generally only one hot gas bypass system will be applied on a two-circuit unit. Connect the hot gas bypass system to Circuit 1 (first-on/last-off, connected to the evaporator coil’s bottom circuit).

38AUD Piping Connections —

The 38AUD’s two circuits are designated Circuit 1 and Circuit 2. Circuit 1 is controlled by the thermostat’s Y1 (or TC1) contact and will be the first circuit on and last circuit off. Circuit 2 is controlled by the thermostat’s Y2 (or TC2) contact and this circuit is always the “lag” circuit.

See Fig. 6 for location of Circuit 1 and Circuit 2 service valves and field piping connections. Circuit 1 is on the left-hand side of the service valve compartment; Circuit 2 is on the right.

When a single piece evaporator coil with two separate circuits is connected to a 38AUD, the lower coil circuit should be connected to the 38AUD’s Circuit 1 so that the evaporator’s lower coil segment is first-on/last-off (to avoid re-evaporation of condensate on dry lower coil segments).

CKT

Circuit 1

Connections

38AU units include one (38AUZ) or two (38AUD) Puron-duty filter drier(s), shipped in cartons attached to the unit basepan. Remove the filter drier(s) and prepare to install in the liquid line(s) at the evaporator coil. Do not remove connection fitting plugs until ready to connect and braze the filter drier into the liquid line position.

Circuit 2

Connections

C10355

Fig. 6 -- 38AUD Service Valve Locations

Plan the Circuit 1 and Circuit 2 tubing segments carefully, mark each segment and check constantly as piping systems are assembled to avoid piping errors.

38AUD unit cannot be field-piped as a single-circuit/tandem system.

Connecting 40RU to 38AUD: The 40RU fan coil in sizes 16, 25 and 28 is a face-split coil design that also has its circuits designated as 1 and 2. See Fig. 7. Note that the lower coil segment changes as the arrangement of the 40RU changes. In a vertical arrangement, the 40RU’s lower coil segment is segment 2; this segment should be connected to the 38AUD’s Circuit 1. In a horizontal arrangement, the 40RU’s lower segment is now segment 1; this segment should be connected to the 38AUD’s Circuit 1.

Note that refrigerant suction piping should be insulated.

40RU Arrangement

Vertical

Horizontal

Cooling

Stage

Y1 Y2

40RU Coil

Segment

2 1

1 2

Connect to

38AUD

Circuit 1 Circuit 2

Install Filter Drier(s) and Moisture Indicator(s) —

FIRS T ON/LA ST OFF = 2

VERTICAL INSTALLATION

FIRS T O N/LAS T OF F = 1

HORIZONTAL INSTALLATION

C10071

Fig. 7 -- Typical Evaporator Coil Connections (40RU)

Table 8 – Puron-duty Filter Drier(s)

Model-Size Qty

38AUZ*16 1

38AUZ*25 1

38AUD*16 2

38AUD*25 2

Liquid

Line OD

/8-in 30 cu. in. KH43LG087

/2-in 16 cu. in. KH43LG085

Desiccant

Volume

Part

Number Ref

38AU

Every unit MUST have a filter drier in the liquid line. 38AUD models require two filter driers (one in each liquid line). Locate the filter drier(s) at the indoor unit, close to the evaporator coil’s thermal expansion valve (TXV) inlets.

Table 9 – Refrigerant Specialties Part Numbers.

LIQUID LINE

SIZE (in.)

38AUD units require TWO sets of parts.

LIQUID LINE

SOLENOID VALVE (LLSV)

EF680035 EF680037 KM680004

EF680036 EF680037 KM680005

Installation of liquid line moisture indicating sightglass in each circuit is recommended. Locate the sightglass(es) between the outlet of the filter drier and the TXV inlet.

Refer to Table 9 for recommendations on refrigeration specialties.

LLSV COIL

SIGHT

GLASS

FILTER

DRIER

provided with unit

see Table 8

8 DIAMS

MIN

8 DIAMS

MIN

8 DIAMS

EQUALIZER LINE

TXV

EQUALIZER LINE

TXV

CKT 2

SIGHT GLASSES B LOCATION

TXV

CKT 1

MIN

SIGHT GLASS A LOCATION

FILTER DRIERS B LOCATION

FILTER DRIER A LOCATION

LIQUID LINE SOLENOID VALVE

SIGHT GLASS A LOCATION

INDOOR COIL CKT

AIRFLOW

INDOOR COIL CKT 2

AIRFLOW

INDOOR COIL CKT 1

38AU

AIRFLOW

TXV SENSING BULB

15 DIAMS

MIN

DIAMS

Single Circuit Coil Piping Configuration

For single compressor condensing units

TXV SENSING BULB

15 DIAMS

MIN

DIAMS

TXV SENSING BULB

15 DIAMS

MIN

DIAMS

Dual Circuit Coil Piping Configuration

For single compressor condensing units

Fig. 8 -- Location of Sight Glass(es) and Filter Driers

Typical 38AUZ Systems

8 DIAMS

MIN

8 DIAMS

EQUALIZER LINE

TXV

CKT 2

TXV

CKT 1

MIN

SIGHT GLASSES

FILTER DRIERS

AIRFLOW

SUCTION CIRCUIT 2

TXV SENSING BULB

15 DIAMS

SUCTION CIRCUIT 1

MIN

DIAMS

TXV SENSING BULB

MIN

DIAMS

Dual Circuit Coil Piping Configuration

For two circuit condensing units

Fig. 9 -- Location of Sight Glasses and Filter Driers

Typical 38AUD Systems

In some applications, depending on space and convenience requirements, it may be desirable to install 2 filter driers and sight glasses in a single circuit application. One filter drier and sight glass may be installed at A locations (see Fig. 8) or 2 filter driers and sight glasses may be installed at B locations (see Figs. 8 and 9).

Select the filter drier for maximum unit capacity and minimum pressure drop. Complete the refrigerant piping

FLOW

FILTER DRIER A LOCATION

LIQUID LINE SOLENOID VALVE

LIQUID LINE SOLENOID VALVE CIRCUIT 2

LIQUID LINE SOLENOID VALVE CIRCUIT 1

FLOW

C10202

FLOW

C10072

from the indoor unit to the outdoor unit before opening the liquid and suction lines at the outdoor unit.

Install Liquid Line Solenoid Valve —

It is recommended that a solenoid valve be placed in the main liquid line (see Figs. 8 & 9) between the condensing unit and the evaporator coil. Locate the solenoid valve at the outlet end of the liquid line, near the evaporator coil connections, with flow direction arrow pointed at the evaporator coil. Refer to Table 9. (A liquid line solenoid valve is required when the liquid line length exceeds 75 ft [23 m].) This valve prevents refrigerant migration (which causes oil dilution) to the compressor during the off cycle, at low outdoor ambient temperatures. Wire the solenoid in parallel with the compressor contactor coil (see Figs. 8 & 9). This means of electrical control is referred to as solenoid drop control.

Solenoid drop control wiring: Control the power to the liquid line solenoid through a Solenoid Valve Relay (SVR) in all units. Use part number HN61PC005 (field--supplied, installed). 38AUZ unit requires one SVR; 38AUD unit requires two relays.

38AUD unit also requires a separate control power transformer for the liquid solenoid valve loads. Select transformer part number according to unit power supply.

Unit Power Transformer Part #

208/230 HT01BD202

460 HT01BD702

575 HT01BD902

Mount the SVR (and transformer TRAN3 when used) in unit control box. Connect per wiring schematic label on unit or per Fig. 29 (38AUZ) or Fig. 30 (38AUD).

Capacity Control Liquid Line Solenoid Valve:

Evaporator capacity staging control via direct thermostat control of a liquid solenoid valve on the evaporator’s second stage circuit is not possible with 38AU models. If this installation is a retrofit for a unit that included automatic pressure--operated unloading, check the existing thermostat and liquid solenoid valve wiring for possible direct thermostat control of a solenoid valve; re--wire per Figs. 17 or 18 and 29 or 30.

Selecting an Accumulator –

Because all 38AU models use scroll compressors, an accumulator is not required. If an accumulator is to be added, check the accumulator manufacturer’s literature carefully for indication of its suitability for use with R--410A; look for minimum working pressure of 200 psig (1380 kPa). Select the accumulator first on the basis of its cataloged minimum capacity (tons) to ensure oil return from the accumulator, then on tube size or holding capacity.

Make Piping Connections —

Piping connections at the 38AU unit are ball valves with stub tube extensions. Do not open the unit service valves until all interconnecting tube brazing has been completed.

The stub tube connections include1/4-in SAE service

fittings with Schrader valve cores (see Fig. 10). Before making any brazed connections to the unit service valves, remove both Schrader valve caps and cores and save for re-installation. Connect a source for nitrogen to one of these service fittings during tube brazing to prevent the formation of copper oxides inside the tubes at brazed joints.

charging. For a cylinder without a dip tube, invert the cylinder (access valve on the bottom) when removing liquid refrigerant.

Because Puron (R--410A) refrigerant is a blend, it is strongly recommended that refrigerant always be removed from the cylinder as a liquid. Admit liquid refrigerant into the system in the discharge line. If adding refrigerant into the suction line, use a commercial metering/expansion device at the gauge manifold; remove liquid from the cylinder, pass it through the metering device at the gauge set and then pass it into the suction line as a vapor. Do not remove Puron (R–410A) refrigerant from the cylinder as a vapor.

Preliminary Charge —

Factory High-Flow

ccess Port

Field Service Access Port (Schrader core)

Before starting the unit, charge R-410A liquid refrigerant

Service Valve with Stem Cap

Sweat Connection

Fig. 10 -- Typical Piping Connection Assembly

C10203

into the high side of each 38AU circuit through the liquid service valve(s). The amount of refrigerant added must be at least 80% of the operating charge listed in Tables 5 or 6 for LINEAR line length LESS the factory charge quantity (if factory shipping charge has not been removed). See

38AU

example below.

When connecting the field tubing to the 38AU service valves, wrap the valves in wet rags to prevent overheating

Pressure-test all joints from outdoor unit connections over to the evaporator coil, using nitrogen as pressure and with soap-and-bubbles.

Allow high and low side pressures to equalize. If pressures do not equalize readily, charge R-410A vapor (using special service manifold with expansion device) into the suction line service port for the low side of system to assure charge in the evaporator. Refer to GTAC II, Module 5, Charging, Recover, Recycling, and Reclamation for liquid

When pressure-testing is completed, remove the nitrogen

charging procedures.

source at the outdoor unit service valves and re-install the two Schrader valve cores. Torque the cores to 2-3 in-lbs (23-34 N-cm).

Evacuation/Dehydration —

Evacuate and dehydrate the connected refrigeration system(s) (excluding the 38AU unit) to 500 microns using a two-stage vacuum pump attached to the service ports outside the 38AU service valves, following description in GTAC II, Module 4, System Dehydration.

WARNING

Example: 38AUD*25 (RTPF) 60-ft (18.3 m) linear line length Equivalent line length 90-ft (27.4 m) Liquid Lift: 20-ft (6.1 m) Select line sizes from Table 6 (38AUD):

Liquid Suction 1-

/2in

/8in.

Charge

Circuit 1: 23.0 lbs (at 75-ft linear length)

UNIT OPERATION AND SAFETY HAZARD

Failure to follow this warning could cause personal injury, death and/or equipment damage.

Puron

(R--410A) refrigerant systems operate at higher pressure than standard R--22 systems. Do not use R--22 service equipment or components on Puron refrigerant equipment.

Circuit 2: 22.0 lbs

80% of Operating Charge:

Circuit 1: 0.80 x 23.0 = 18.4 lbs

Circuit 2: 0.80 x 22.0 = 17.6 lbs Factory Shipping Charge: 15 lbs Field-Charge

Circuit 1: 18.4 -- 15 = 3.4 lbs

This unit is designed for use with Puron (R--410A) refrigerant. Do not use any other refrigerant in this system.

Puron (R--410A) refrigerant is provided in pink (rose) colored cylinders. These cylinders are available with and without dip tubes; cylinders with dip tubes will have a label indicating this feature. For a cylinder with a dip tube, place the cylinder in the upright position (access valve at the top) when removing liquid refrigerant for

Circuit 2: 17.6 -- 15 = 2.6 lbs For linear line lengths longer than 125 ft (38 m), contact

your local Carrier representative for system charge value.

Step 6 — Install Accessories

Accessories requiring modifications to unit wiring should be completed now. These accessories may include Winter Start controls and Low Ambient controls. Refer to the instructions shipped with the accessory.

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