Carrier 38AKS013-024 User Manual

Air-Cooled Condensing Units

Installation, Start-Up and

Service Instructions

38AKS013-024

50/60 Hz

CONTENTS

Page

SAFETY CONSIDERATIONS ...................1

INSTALLATION .............................1-12

Step 1 — Complete Pre-Installation

Checks ....................................1

Step 2 — Rig and Mount the Unit .............8

Step 3 — Complete Refrigerant Piping

Connections ...............................8

Step 4 — Install Accessories ................10

Step 5 — Complete Electrical

Connections ..............................10

PRE-START-UP .............................12

System Check ..............................12

Leak Test and Dehydration ..................12

Turn On Crankcase Heater ...................12

Preliminary Charge ..........................12

START-UP ................................13-16

Preliminary Checks .........................13

Preliminary Oil Charge ......................13

Start Unit ...................................13

Adjust Refrigerant Charge ...................13

Check Compressor Oil Level ................13

Final Checks ................................13

OPERATING SEQUENCE ....................17

Cooling .....................................17

Heating .....................................17

Fan Cycling .................................17

Winter Start Control .........................17

SERVICE ..................................17-19

Capacity Control ............................17

Head Pressure Control ......................17

Time GuardT II Circuit .......................17

Winter Start Control .........................18

Crankcase Heater ...........................18

Compressor Protection ......................18

High-Pressure Switches .....................18

Low-Pressure Switches .....................18

Outdoor Fans ...............................18

Lubrication .................................18

Cleaning Coils ..............................18

TROUBLESHOOTING ......................20,21

START-UP CHECKLIST ................CL-1,CL-2

SAFETY CONSIDERATIONS

Installing, starting up, and servicing air-conditioning equip­ment can be hazardous due to system pressures, electrical
components, and equipment location (roofs, elevated struc­tures, etc.).

Only trained, qualified installers and service mechanics

should install, start-up, and service this equipment (Fig. 1).

Untrained personnel can perform basic maintenance func­tions such as cleaning coils. All other operations should be
performed by trained service personnel.

When working on the equipment, observe precautions in
the literature and on tags, stickers, and labels attached to the
equipment.

Follow allsafetycodes.Wear safetyglassesandworkgloves.
Keep quenching cloth and fire extinguisher nearby when braz­ing. Use care in handling, rigging, and setting bulky equip­ment.

ELECTRIC SHOCK HAZARD
Separate power sources (main and control

power circuits) are used for these units. Be
sure both main and control power circuits are
disconnected before servicing.

INSTALLATION

Step 1 — Complete Pre-Installation Checks

UNCRATE 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 claim with shipping com­pany if shipment is damaged or incomplete.

CONSIDER SYSTEM REQUIREMENTS

• Consult local building codes and National Electrical Code

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

• Allow sufficient space for airflow clearance, wiring,

refrigerant piping, and servicing unit. See Fig. 1. See
Fig. 2 for unit component locations.

• Locate unit so that outdoor coil (condenser) airflow is un-

restricted on all sides and above.

• Unit may be mounted on a level pad directly on the base

channels or mounted on raised pads at support points. See
Tables 1A-1D for unit operating weights. See
T able2forweightdistributionbasedonrecommendedsup­port points.

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

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book 1 4
Tab 3a 2a

PC 111 Catalog No. 563-701 Printed in U.S.A. Form 38AKS-3SI Pg 1 9-98 Replaces: 38AKS-2SI

NOTE: Service areas — Allow 3 ft (914 mm) on both sides and 2 ft (610 mm)
on both ends of unit for servicing.

2

Fig. 1 — Dimensions

1324567

12 91011

LEGEND

1—No. 1 Fan 5—No. 2 Fan 9—Compressor
2—High-Pressure Switch 6—Terminal Block 1 (Unit Power) 10 — Low-Pressure Switch
3—Circuit Breaker — Control Circuit 7—Terminal Block 2 (Control Power) 11 — Hot Gas Bypass Piping Stub (
4—Circuit Breakers — Power Circuits 8—Wraparound Coil 12 — Muffler

Fig. 2 — Component Locations (Typical)

8

3

⁄8-in. ODM)

3

Table 1A — Physical Data (English, 60 Hz)

UNIT 38AKS 013 014 016 024
OPERATING WEIGHT (lb)

With Aluminum-Fin Coil 732 779 789 900
With Copper-Fin Coil 825 919 929 1040

REFRIGERANT* R-22

Shipping Charge (lb) 2.1 3.1 3.1 3.1
Operating Charge, Typical (lb)† 22 23 23 28

COMPRESSOR Reciprocating, Semi-Hermetic

Model 06DD824 06DD328 06DD537 06EA250
No. Cylinders 6664
Speed (rpm) 1750
Capacity Steps (%)

Accessory 33**,66,100 33**,66,100 33**,66,100 —
Standard 66,100 66,100 66,100 50,100

Crankcase Heater Watts 125
Unloader Setting (psig)

Load 70±1

Unload 60±2
OIL CHARGE (pt) 10 10 10 15.5
CONDENSER FANS Axial Flow, Direct Drive

Quantity...Diameter (in.) 2...26
Nominal Hp
Nominal Airflow (cfm, total) 11,000
Speed (rpm) 1,075
Watts (total) 1,460

CONDENSER COIL Copper Tubes, Aluminum Fins

Rows...Fins/in. 2...15 3...15 3...15 3...15
Total Face Area (sq ft) 29.2 29.2 29.2 29.2
Storage Capacity (lb)†† 27.2 40.3 39.8 39.8

CONTROLS

Pressurestat (psig)

High Pressure

Cutout 395±10
Cut-in 295±20

Low Pressure

Cutout 27±4
Cut-in 67+7

FAN CYCLING CONTROLS

No 2 Fan:

Close (psig) 255±10

Open (psig) 160±10
PRESSURE RELIEF Fusible Plug

Location Compressor Compressor Compressor Liquid Line
Temperature (F) 200 200 200 210

PIPING CONNECTIONS (in. ODM)

Suction 1
Liquid
Hot Gas Stub

*Unit is factory supplied with holding charge only.

†With 25 ft of interconnecting piping. Operating charge is approximate for maximum system capacity.

**Indicates capacity step (%) with electric unloader accessory.

††Storage capacity is measured at liquid saturated temperatures of 125 F for 38AKS013, 123 F for

38AKS014, and 130 F for 38AKS016 and 024.

1

⁄

8

13⁄

8

1

⁄

2

13⁄

5

⁄

8

3

⁄

8

8

15⁄

8

4

Table 1B — Physical Data (SI, 60 Hz)

UNIT 38AKS 013 014 016 024
OPERATING WEIGHT (kg)

With Aluminum-Fin Coil 332 353 358 408
With Copper-Fin Coil 374 417 421 472

REFRIGERANT* R-22

Shipping Charge (kg) 0.95 1.40 1.40 1.40
Operating Charge, Typical (kg)† 10.0 10.4 10.4 12.7

COMPRESSOR Reciprocating, Semi-Hermetic

Model 06DD824 06DD328 06DD537 06EA250
No. Cylinders 6664
Speed (r/s) 29.2
Capacity Steps

Accessory 33**,66,100 33**,66,100 33**,66,100 —
Standard 66,100 66,100 66,100 50,100

Crankcase Heater Watts 125
Unloader Setting (kPa)

Load 483 ± 6.9

Unload 414 ± 13.8
OIL CHARGE (L) 4.73 4.73 4.73 7.33
CONDENSER FANS Axial Flow, Direct Drive

Quantity...Diameter (mm) 2...660
Nominal kW 0.37
Nominal Airflow (L/s, total) 5566
Speed (r/s) 17.9
Watts (total) 1460

CONDENSER COIL Copper Tubes, Aluminum Fins

Rows...Fins/m 2...590 3...590 3...590 3...590
Total Face Area (sq m) 2.71 2.71 2.71 2.71
Storage Capacity (kg)†† 12.3 18.3 18.1 18.1

CONTROLS

Pressurestat (kPa)

High Pressure

Cutout 2724 ± 69
Cut-in 2034 ± 138

Low Pressure

Cutout 186 ± 28
Cut-in 462 + 48

FAN CYCLING CONTROLS

No 2 Fan:

Close (kPa) 1758 ± 69

Open (kPa) 1103±69
PRESSURE RELIEF Fusible Plug

Location Compressor Compressor Compressor Liquid Line
Temperature (C) 93.3 93.3 93.3 98.9

PIPING CONNECTIONS (in. ODM)

Suction 1
Liquid
Hot Gas Stub

*Unit is factory supplied with holding charge only.

†With 7.6mof interconnecting piping. Operatingchargeisapproximate for maximum systemcapacity.

**Indicates capacity step (%) with electric unloader accessory.

††Storage capacity is measured at liquid saturated temperatures of 51.7 C for 38AKS013, 50.6 C for

38AKS014, and 54.4 C for 38AKS016 and 024.

1

⁄

8

13⁄

8

5

⁄

8

3

⁄

8

13⁄

8

15⁄

8

5

Table 1C — Physical Data (English, 50 Hz)

UNIT 38AKS 013 014 016 024
OPERATING WEIGHT (lb)

With Aluminum-Fin Coil 732 779 789 900
With Copper-Fin Coil 825 919 929 1040

REFRIGERANT* R-22

Shipping Charge (lb) 2.1 3.1 3.1 3.1
Operating Charge, Typical (lb)† 22 23 23 28

COMPRESSOR Reciprocating, Semi-Hermetic

Model 06DD824 06DD328 06DD537 06EA250
No. Cylinders 6664
Speed (rpm) 1450
Capacity Steps

Accessory 33**,66,100 33**,66,100 33**,66,100 —
Standard 66,100 66,100 66,100 50,100

Crankcase Heater Watts 125
Unloader Setting (psig)

Load 70±1

Unload 60±2
OIL CHARGE (pt) 10 10 10 15.5
CONDENSER FANS Axial Flow, Direct Drive

Quantity...Diameter (in.) 2...26
Nominal Hp
Nominal Airflow (cfm, total) 9210
Speed (rpm) 900
Watts (total) 1050

CONDENSER COIL Copper Tubes, Aluminum Fins

Rows...Fins/in. 2...15 3...15 3...15 3...15
Total Face Area (sq ft) 29.2 29.2 29.2 29.2
Storage Capacity (lb)†† 27.2 40.3 39.8 39.8

CONTROLS

Pressurestat (psig)

High Pressure

Cutout 395±10
Cut-in 295±20

Low Pressure

Cutout 27±4
Cut-in 67+7

FAN CYCLING CONTROLS

No 2 Fan:

Close (psig) 255±10

Open (psig) 160±10
PRESSURE RELIEF Fusible Plug

Location Compressor Compressor Compressor Liquid Line
Temperature (F) 200 200 200 210

PIPING CONNECTIONS (in. ODM)

Suction 1
Liquid
Hot Gas Stub

*Unit is factory supplied with holding charge only.

†With 25 ft of interconnecting piping. Operating charge is approximate for maximum system capacity.

**Indicates capacity step (%) with electric unloader accessory.

††Storage capacity is measured at liquid saturated temperatures of 125 F for 38AKS013, 123 F for

38AKS014, and 130 F for 38AKS016 and 024.

1

⁄

8

13⁄

8

1

⁄

2

13⁄

5

⁄

8

3

⁄

8

8

15⁄

8

6

Table 1D — Physical Data (SI, 50 Hz)

UNIT 38AKS 013 014 016 024
OPERATING WEIGHT (kg)

With Aluminum-Fin Coil 332 353 358 408
With Copper-Fin Coil 374 417 421 472

REFRIGERANT* R-22

Shipping Charge (kg) 0.95 1.40 1.40 1.40
Operating Charge, Typical (kg)† 10.0 10.4 10.4 12.7

COMPRESSOR Reciprocating, Semi-Hermetic

Model 06DD824 06DD328 06DD537 06EA250
No. Cylinders 6664
Speed (r/s) 24.2
Capacity Steps

Accessory 33**,66,100 33**,66,100 33**,66,100 —
Standard 66,100 66,100 66,100 50,100

Crankcase Heater Watts 125
Unloader Setting (kPa)

Load 483 ± 6.9

Unload 414 ± 13.8
OIL CHARGE (L) 4.73 4.73 4.73 7.33
CONDENSER FANS Axial Flow, Direct Drive

Quantity...Diameter (mm) 2...660
Nominal kW 0.37
Nominal Airflow (L/s, total) 4660
Speed (r/s) 15.0
Watts (total) 1050

CONDENSER COIL Copper Tubes, Aluminum Fins

Rows...Fins/m 2...590 3...590 3...590 3...590
Total Face Area (sq m) 2.71 2.71 2.71 2.71
Storage Capacity (kg)†† 12.3 18.3 18.1 18.1

CONTROLS

Pressurestat (kPa)

High Pressure

Cutout 2724 ± 69
Cut-in 2034 ± 138

Low Pressure

Cutout 186 ± 28
Cut-in 462 + 48

FAN CYCLING CONTROLS

No 2 Fan:

Close (kPa) 1758 ± 69

Open (kPa) 1103±69
PRESSURE RELIEF Fusible Plug

Location Compressor Compressor Compressor Liquid Line
Temperature (C) 93.3 93.3 93.3 98.9

PIPING CONNECTIONS (in. ODM)

Suction 1
Liquid
Hot Gas Stub

*Unit is factory supplied with holding charge only.

†With 7.6mof interconnecting piping. Operatingchargeisapproximate for maximum systemcapacity.

**Indicates capacity step (%) with electric unloader accessory.

††Storage capacity is measured at liquid saturated temperatures of 51.7 C for 38AKS013, 50.6 C for

38AKS014, and 54.4 C for 38AKS016 and 024.

1

⁄

8

13⁄

8

5

⁄

8

3

⁄

8

13⁄

8

15⁄

8

7

Table2—Weight Distribution

WEIGHT

UNIT

38AKS

013 732 332 94 43 93 42 93 42 149 68 151 68 152 69
013C 825 374 119 54 116 53 115 52 157 71 159 72 159 72
014 779 353 95 43 94 43 94 43 164 74 166 75 166 75
014C 919 417 131 59 129 59 128 58 176 80 177 80 178 81
016 789 358 95 43 95 43 96 44 167 76 168 76 168 76
016C 929 421 131 59 130 59 130 59 178 81 180 82 180 82
024 900 408 119 54 114 52 113 51 179 81 185 84 190 86
024C 1040 472 155 70 150 68 146 66 191 87 196 89 202 92

Total

Operating

lb kg lb kg lb kg lb kg lb kg lb kg lb kg

ABCDEF

Support Point

Step 2 — Rig and Mount the Unit

Be sure unit panels are securely in place prior to
rigging.

RIGGING — These units are designed for overhead rigging
only. For this purpose, the transverse base channels extend
beyond the sides of the unit, with holes provided in the end
plates to attach cables or hooks. Rig with top skid packaging
assembly in place to prevent unit damage by the rigging cable.
As further protection for the coil faces, plywood sheets can
be placed against the sides of the unit, behind the cables.
Run the cables to acentral 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 unit from the rails or pad when
unit is in final position.

COMPRESSOR MOUNTING — As shipped, the compres­sor is held tightly in place by self-locking bolts. Before start-

ing unit, loosen self-locking bolts until the snubber washer
can be moved sideways with finger pressure. Do not
remove shipping bolts. See Fig. 3.

Step 3 — Complete Refrigerant Piping
Connections

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

SIZE REFRIGERANT LINES — Consider the length of pip­ing required between outdoor unit and indoor unit (evapo­rator), the amount of liquid lift, and compressor oil return.
See Tables 3-5B and also refer to Part 3 of Carrier System
Design Manual and E20-IIt software for design details and
line sizing. Refer to indoor unit installation instructions for
additional information.

NOTE: Use the piping data in Tables3-5Bas a general guide
only. For more precise calculations, refer to Carrier System
Design manual or E20-II software.

Condensing units with multiple-step unloading may
require double suction risers to assure proper oil return at
minimum load operating condition. See Tables 4A-5B and
Fig. 4. Reduction of evaporator coil surface should be ana­lyzed to provide sufficient refrigerant velocity to return oil
to the compressor. Liquid line solenoid valves may be used
in certain situations to accomplish this. Hot gas bypass, if
used, should be introduced before the evaporator.

Note that refrigerant suction piping should be insulated.

Table 3 — Liquid Line Data

MAXIMUM

ALLOWABLE

LIQUID LIFT

UNIT

38AKS

013 52 (15.8)

014 67 (20.4)

016 82 (25.0

024 87 (26.5) 86 (26)

*Inlet and outlet.
NOTE: Data shown is for units operating at 45 F (7.2 C) saturated

suction and 95 F (35 C) entering air.

ft (m)

60 Hz 50 Hz

Maximum
Allowable

Pressure

Drop

psig (kPa)

7 (48.3) 2 (1.1)

LIQUID LINE

Maximum
Allowable

Temp.

Loss
F (C)

Filter Drier

and

Sight Glass

Flare Conn.*

in. (mm)

5

⁄8(15.88)

Fig. 3 — Compressor Mounting

8

Table 4A — Refrigerant Piping Sizes — 60 Hz Units

Table 5A — Refrigerant Piping Sizes — 50 Hz Units

LENGTH OF INTERCONNECTING PIPING, FT (M)

UNIT

38AKS

0-15

(0-4.5)

15-25

(4.5-7.5)

Line Size (in. OD)

25-50

(7.5-15)

50-75

(15-23)

75-100
(23-30)

LSLSLSLSLS

1

013
0141⁄211⁄
016
0245⁄815⁄

⁄211⁄

1

⁄213⁄

8
8
8
8

1

⁄211⁄

1

⁄213⁄

5

⁄813⁄

5

⁄815⁄

5

8

⁄813⁄

5

8

⁄813⁄

5

8

⁄815⁄

7

8

⁄815⁄

5

8

⁄813⁄

8

5

8

⁄815⁄8*7⁄815⁄8*

7

8

⁄815⁄

8

7

8

⁄821⁄

8

5

⁄815⁄8*

7

⁄821⁄8*

7

⁄821⁄

8

LEGEND

L—Liquid
S—Suction

Close-coupled.

*Requires a double suction riser if 2 unloaders are used and the

evaporator is below the condensing unit. See Table 4B and Fig. 4
for more information.

NOTES:

1. Pipe sizes are based ona2F(1.1 C) loss for liquid lines and a

1.5 F (0.8 C) loss for suction lines.

2. Pipe sizes are based on an equivalent length equal to the maxi­mum lengthof interconnecting pipingplus50% for fittings.Amore
accurate estimate may result in smaller sizes.

3. Line size conversion to mm:

in. mm

1

⁄

2

5

⁄

8

7

⁄

8

11⁄

8

3

1

⁄

8

15⁄

8

21⁄

8

12.7

15.9

22.2

28.6

34.9

41.3

54.0

Table 4B — Refrigerant Piping Sizes,

Double Suction Risers — 60 Hz Units

LENGTH OF INTERCONNECTING PIPING, FT (M)

UNIT

38AKS

50-75

(15-23)

Line Size (in. OD)

ABCABC

013 ———1
014 11⁄
016 ———1

NOTES:

1. See Fig. 4 for ‘‘A,’’ ‘‘B,’’ and ‘‘C’’ dimensions.

2. No double suction risers are needed for unit size 024.

3. See Table 4A for line size conversion to mm.

8

13⁄

8

15⁄

8

75-100
(23-30)

1

⁄81

11⁄

3

⁄81

3

8

13⁄

5

⁄81
⁄82

5

⁄

8

8

15⁄

8

1

⁄

8

LENGTH OF INTERCONNECTING PIPING, FT (M)

COND

UNIT

38AKS

0-15

(0-4.5)

15-25

(4.5-7.5)

Line Size (in. OD)

25-50

(7.5-15)

50-75

(15-23)

75-100
(23-30)

LSLSLSLSLS

1

013
0141⁄211⁄
016
0245⁄813⁄

*Requiresadouble suctionriserif 2unloadersare usedandthe evapo-

rator is belowthecondensingunit. See Table 5B andFig.4for more
information.

NOTES:

1. Pipe sizes are based on 2 F (1.1 C) max loss for liquid lines and

2. Pipe sizes are based on an equivalent length equal to the maxi-

3. See Table 4A for line size conversion to mm.

⁄211⁄

5

⁄813⁄

1.5F(0.8 C)maxloss for suctionlines, selected atmaximum length
for each interval and for matched systems at nominal rating con­ditions, nominal airflow.

mum length ofinterconnectingpipingplus 50% for fittings.Amore
accurate estimate may result in smaller sizes.

8
8
8
8

1

⁄211⁄

5

⁄813⁄

5

⁄813⁄

5

⁄813⁄

5

8

⁄813⁄

5

8

⁄813⁄

5

8

⁄815⁄8*7⁄815⁄8*7⁄815⁄8*

5

8

⁄815⁄

5

8

⁄813⁄

7

8

⁄815⁄8*7⁄815⁄8*

7

8

⁄815⁄

8

8

5

⁄813⁄8*

7

⁄815⁄

8

Table 5B — Refrigerant Piping Sizes,

Double Suction Risers — 50 Hz Units

LENGTH OF INTERCONNECTING PIPING FT (M)

COND

UNIT

38AKS

25-50

(7.5-15)

ABCABCABC

013 ——————1
014 ———11⁄813⁄815⁄811⁄813⁄815⁄
016 11⁄813⁄815⁄811⁄813⁄815⁄811⁄813⁄815⁄

NOTES:

1. See Fig. 4 for ‘‘A,’’ ‘‘B,’’ and ‘‘C’’ dimensions.

2. Double suction risers are not required for unit size 024.

3. See Table 4A for line size conversion to mm.

50-75

(15-23)

Line Size (in. OD)

75-100
(23-30)

1

⁄813⁄815⁄

8
8
8

LEGEND

Suction Riser
Suction Riser

Without
With

Trap

Trap

Suction Line to Condensing Unit
Short Vertical Riser Into

Condensing Unit:

38AKS013 — 1
38AKS014,016 — 1
38AKS024 — 1

1

⁄8in. OD

3

⁄8in. OD

5

⁄8in. OD

Fig. 4 — Suction Line Piping

9

INSTALL FILTER DRIER(S) AND MOISTURE INDICA­TOR(S) — Every unit should have a filter drier and liquid­moisture indicator(sightglass).Insome applications, depending
on space and convenience requirements, it may be desirable
to install 2 filter driers and sight glasses. One filter drier and
sight glass may be installed at A locations in Fig. 5. Or, 2
filter driers and sight glasses may be installed at B locations.

Select the filter drier for maximum unit capacity andmini­mum pressure drop. Complete the refrigerant piping from
indoor unit to outdoor unit before opening the liquid and suc­tion lines at the outdoor unit.

2. Remove

1

⁄4-in. flare cap from liquid valve Schrader port.

3. Attach refrigerant recovery device and recover holding
charge.

4. Remove runaround loop.

5. Install a field-supplied liquid moisture indicator in the pip­ing immediately leaving outdoor unit.

6. If necessary, install field-supplied thermostatic expan­sion valve(s) (TXVs) in air handler.

If 2 TXVs are installed and two-step cooling is desired,
install field-supplied liquid line solenoid valve ahead of the
upper TXV (see Fig. 5).

PROVIDE SAFETY RELIEF — A fusible plug is located
on the compressor crankcase or in the liquid line (Fig. 6).
Do not cap this plug. If local code requires additional safety
devices, install them as directed.

TXV — Thermostatic Expansion Valve

Fig. 5 — Location of Sight Glass(es)

and Filter Drier(s)

INSTALL LIQUID LINE SOLENOID VALVE — SOLE­NOID DROP — It is recommended that a solenoid valve be
placed in the main liquid line (see Fig. 5) between condens­ing unit (38AKS) and fan coil (40RM, 39 Series). (A liquid
line solenoid valve is required when the liquid line length
exceeds 100 ft [30.5 m] or when the condensing unit is con­nected to a chiller barrel in a built-up chiller system.) This
valve prevents refrigerant migration (which causes oil dilu­tion) to the compressor during the off cycle at low outdoor
ambient temperatures. The solenoid should be wired in par­allel with the compressor contactor coil. This means of elec­trical control is referred to as solenoid drop control.

INSTALL LIQUID LINE SOLENOID VALVE (Optional)
— CAPACITY CONTROL — If 2-step cooling is desired,
place a solenoid valve in the location shown in Fig. 5.

MAKE PIPING CONNECTIONS — Do not remove run­around loop from suction and liquid line stubs in the com­pressor compartment until piping connections are ready to
be made. Pass nitrogen or other inert gas through piping while
brazing to prevent formation of copper oxide.

Recover holding charge prior to removal of runaround
piping loop.

NOTE: 38AKS024 has a fusible plug in the liquid line.

Fig. 6 — Location of Fusible Plug (38AKS)

Step 4 — Install Accessories — Field install

accessories such as winter start control or low-ambient con­trol before proceeding with wiring. Refer to the instructions
shipped with the accessory.

Step 5 — Complete Electrical Connections

POWER WIRING — Unit is factory wired for voltage shown
on nameplate. Provideadequatefuseddisconnectswitchwithin
sight from unit and readily accessible from unit, but out of
the reach of children. Lock switch open (off)topreventpower
from being turned on while unit is being serviced. Dis­connect switch, fuses, and field wiring must comply with
national and local code requirements. SeeTables 6A and 6B.

Route power wires through opening in unit end panel to
connection in unit control box as shown on unit label dia­gram and in Fig. 7. Unit must be grounded.

Affix crankcase heater warning sticker to unit disconnect
switch.

CONTROL CIRCUIT WIRING — Control voltage is 24 v.
See Fig. 8 and unit label diagram for field-supplied wiring
details. Route control wires through opening in unit end panel
to connection in unit control box.

1. Open service valves:
a. Discharge service valve on compressor.
b. Suction service valve on compressor.
c. Liquid line valve.

10

LEGEND

EQUIP GND — Equipment Ground
NEC — National Electrical Code

Factory Wiring
Field Wiring

Fig. 7 — Main Power Supply Wiring

Table 6A — Electrical Data (3 Ph/60 Hz)

UNIT COMPR FAN MOTORS (Single Phase)

LEGEND

Volts

Supplied*

Min Max 1 2

MCA ICF

UNIT

38AKS

013

014

016

024

FLA — Full Load Amps (Fan Motors)
ICF — Maximum Instantaneous Current Flow during start-up

kW — Total Fan Motor Input (kilowatts)
LRA — Locked Rotor Amps
MCA — Minimum Circuit Amps per NEC (U.S.A.),

MOCP — Maximum Overcurrent Protection (amps)
RLA — Rated Load Amps (Compressor)

Model

501 208-230 187 253 62.5 178 100 43.6 170
201 380 342 418 35.0 101 50 24.0 93 4.3 3.7
601 460 414 528 29.1 81 40 20.0 77 2.3 1.9
101 575 518 660 22.8 67 35 15.7 62 1.8 1.8

501 208-230 187 253 69.3 199 100 49.3 191
201 380 342 418 38.0 112 60 26.5 104 4.3 3.7
601 460 414 528 31.7 84 50 22.1 80 2.3 1.9
101 575 518 660 25.6 73 40 17.9 69 1.8 1.8

501 208-230 187 253 87.5 274 125 63.6 266
201 380 342 418 49.3 153 80 36.0 145 4.3 3.7
601 460 414 528 40.7 124 60 29.3 120 2.3 1.9
101 575 518 660 33.0 100 50 23.8 96 1.8 1.8

501 208-230 187 254 93.4 353 150 67.9 345
201 380 342 418 49.7 199 80 34.6 191 4.3 3.7
601 460 414 508 48.1 177 80 34.7 173 2.3 1.9
101 575 518 632 40.1 124 60 28.8 120 1.8 1.8

(LRA of compressor plus total FLA of fan motors)

Section 430-24

Nameplate

C—Compressor Contactor
HD — Heating Device
IFC — Indoor-Fan Contactor
LLSV1 — Liquid Line Solenoid Valve 1 — Refrigerant Migration

LLSV2 — Liquid Line Solenoid Valve 2 — Capacity Control
R—Relay

NOTES:

1. Combination LLSV plus IFC va should not exceed 30 va.

2. Do not exceed 5 va (24 vac) per coil.

3. If va values shown in Notes 1 and 2 must be exceeded, use
accessory relay transformer package 38AE900001 (60 Hz) or
38AD900003 (50 Hz and 380-3-60).

Control

Factory Wiring
Field Wiring

LEGEND

Fig. 8 — Remote Thermostat Wiring

MOCP

(Fuse
Only)

RLA LRA

*Units are suitable for use on electrical systems where voltage sup-

plied to the unit terminals is not below or above the listed limits.
NOTES:

1. The MCA and MOCP values are calculated in accordance
with the National Electrical Code (NEC) article 440 (U.S.A.
standard).

2. Motor RLA and LRA values are established in accordance
with Underwriters’ Laboratories (UL) Standard 1995 (U.S.A.
standard).

Total
Fans

2

2

2

2

FLA (ea)

Fan No.

4.3 3.7

4.3 3.7

4.3 3.7

4.3 3.7

kW

1.41

1.41

1.41

1.41

11

Table 6B — Electrical Data (3 Ph/50 Hz)

UNIT COMPR FAN MOTORS 230 v (Single Phase)

UNIT

38AKS

013

014

016

024

FLA — Full Load Amps (Fan Motors)
ICF — Maximum Instantaneous Current Flow during start-up

kW — Total Fan Motor Input (kilowatts)
LRA — Locked Rotor Amps
MCA — Minimum Circuit Amps per NEC (U.S.A.),

MOCP — Maximum Overcurrent Protection (amps)
RLA — Rated Load Amps (Compressor)

Model

803 230 198 264 47.5 134 75 32.9 128
903 400 342 457 31.4 80 50 20.0 74

803 230 198 264 51.0 149 75 35.7 143
903 400 342 457 34.0 89 50 22.1 83

803 230 198 264 66.9 206 100 47.9 200
903 400 342 457 43.0 121 60 29.3 115

803 230 198 254 91.8 213 150 67.9 207
903 400 342 440 50.2 179 80 34.6 173

(LRA of compressor plus total FLA of fan motors)

Section 430-24

Nameplate

Volts

LEGEND

Supplied*

Min Max 1 2

MCA ICF

MOCP

(Fuse
Only)

RLA LRA

*Units are suitable for use on electrical systems where voltage sup-

plied to the unit terminals is not below or above the listed limits.
NOTES:

1. The MCA and MOCP values are calculated in accordance
with the National Electrical Code (NEC) article 440 (U.S.A.
standard).

2. Motor RLA and LRA values are established in accordance
with Underwriters’ Laboratories (UL) Standard 1995 (U.S.A.
standard).

Total
Fans

2 2.9 3.5 1.20
2 2.9 3.5 1.20
2 2.9 3.5 1.20

2 2.9 3.5 1.20303 346 311 380 51.5 121 80 33.3 115

FLA (ea)

Fan No.

kW

PRE-START-UP

IMPORTANT: Before beginning Pre-Start-Up or
Start-Up, review Start-Up Checklist at the back of this
book. The Checklist assures proper start-up of a unit
and provides a record of unit condition,application re­quirements, system information, and operation at ini­tial start-up.

Do not attempt to start the condensing unit, even
momentarily, until the following steps have been com­pleted. Compressor damage may result.

System Check

1. Check all air handler(s) andotherequipmentauxiliarycom­ponents. Consult the manufacturer’s instructions regard­ing any other equipment connected to the condensing unit.
If unit has field-installed accessories, be sure all are prop­erly installed and correctly wired. If used, airflow switch
must be properly installed.

2. Backseat (open) compressor suction and discharge valves.
Now close valves one turn to allow refrigerant pressure
to reach test gages.

3. Open liquid line service valve.

4. Check tightness of all electrical connections.

5. Compressor oil level should be visible in sight glass. See
Fig. 9. Adjust the oil level as required. Refer to Pre­liminary Oil Charge section. No oil should be removed
unless the crankcase heater has been energized for at least
24 hours.

6. Be sure unit is properly leak checked, dehydrated, and
charged. See Preliminary Charge, this page.

7. Electrical power source must agree with nameplate
rating.

8. Crankcase heater must be firmly locked into compressor

crankcase. Be sure crankcase is warm (heater mustbe on
for 24 hours before starting compressor).

9. Be sure compressor floats freely on the mounting springs
and that snubber washers can be moved with finger pres­sure. See Compressor Mounting, page 8, and Fig. 3 for
loosening compressor bolts.

Leak Test and Dehydration — Leak test the entire

refrigerant system using soap bubbles and/or an electronic
leak detector. Evacuate and dehydrate entire refrigerant sys­tem by use of methods described in GTAC II, Module 4,
System Dehydration.

T urnOn Crankcase Heater — Turnoncrankcaseheater

for 24 hours before starting the unit to be sure all the
refrigerantis out of the oil. Toenergizethecrankcase heater,

proceed as follows:

1. Set the space thermostat set point above the space tem­perature so there is no demand for cooling.

2. Close the field disconnect.

3. Turn the fan circuit breaker on. Leave the com­pressor circuit breakers off. The crankcase heater is now
energized.

Preliminary Charge — Refer to GTAC II, Module 5,

Charging, Recovery, Recycling, and Reclamation for charg­ing methods and procedures. Charge each system with R-22
by the liquid charging method (through liquid service valve)
on the high side. Charge according to the values in the
Charging Chart, Fig. 10, 11, or 12.

12

START-UP

Compressor crankcase heater must be on for 24 hours
before start-up. After the heater has been on for 24 hours,
the unit can be started. If no time has elapsed since the pre­liminary charge step has been completed, it is unnecessary
to wait the 24-hour period.

Preliminary Checks

1. Ensure that compressor service valves are backseated.

2. Verify that each compressor floats freely on its mounting

springs.

3. Check that electric power supply agrees with unit name-

plate data.

4. Verify that compressor crankcase heater is securely in place.

5. Check that compressor crankcase heater has been on at

least 24 hours.

6. Note that compressor oil level isvisible in the sight glass.

7. Recheck for leaks using same procedure as pre-

viously outlined in Pre-Start-Up section, Leak Test and
Dehydration.

8. If any leaks are detected, evacuate and dehydrate as pre-

viously outlined in Pre-Start-Up section, Leak Test and
Dehydration.

9. All internal wiring connections must be tight, and all bar-

riers and covers must be in place.

Preliminary Oil Charge — Compressor is factory

charged with oil (see Tables 1A-1D). When oil is checked at
start-up, it may be necessary to add or remove oil to bring
it to the proper level. One recommended oil level adjust­ment method follows:

ADD OIL — Close suction service valve and pump down
crankcase to 2 psig (14 kPag). (Low-pressure switch must
be jumpered.) Wait a few minutes and repeat until pressure
remains steady at 2 psig (14 kPag). Remove oil fill plug above
the oil level sight glass, add oil through plug hole, and
replace plug. Run compressor for 20 minutes and check oil
level. See Fig. 9.

NOTE: Use only Carrier approved compressor oil. Ap­proved sources are:

Petroleum Specialties Inc. ................Cryol 150A

Texaco, Inc. .........................Capella WF-32

Witco Chemical Co. .....................Suniso 3GS

Do not use oil that has been drained out, or oil that has
been exposed to atmosphere.

REMOVE OIL — Pump down compressor to 2 psig
(14 kPag). Loosen the
pressor base and allow the oil to seep out past the threads
of the plug.

NOTE: The crankcase will be slightly pressurized. Do not
remove the plug, or the entire oil charge will be lost.

Small amounts of oil can be removed through the oil pump
discharge connection while the compressor is running.

1

⁄4-in. (6.4 mm) pipe plug at the com-

Never charge liquid into the low-pressure side of sys­tem. Do not overcharge. During charging or removal of
refrigerant, be sure indoor-fan system is operating.

Adjust Refrigerant Charge

NOTE: Actual start-up and all refrigerant charge modifica­tions should be done only under supervision of a qualified
refrigeration mechanic.

With all fans operating, adjust the refrigerant charge in
accordance with the unit charging charts located on the
inside of the control box doors and in Fig. 10-12.

Measure pressure at the liquid line service valve, being
sure Schrader depressor is used if required. Also, measure
liquid line temperature as close to the liquid service valve as
possible.Add chargeuntil the pressure and temperature con­ditions of the charging chart curve are met. If liquid pressure
and temperature point fall above curve, add charge. If liquid
pressure and temperature point fall below curve, reduce the
charge until the conditions match the curve.

If the sight glass is cloudy, check refrigerantchargeagain.
Ensure all fans are operating. Also ensure maximum
allowable liquid lift has not been exceeded. If charged per
chart and if the sight glass is stillcloudy, check fora plugged
filter drier or a partially closed solenoid valve. Replace or
repair, as needed.

Check Compressor Oil Level— After adjusting the

refrigerant charge, allow the compressor to run fully loaded
for 20 minutes. Running oil level should be within view of
the crankcase sight glass. Stop the compressor at the field
power supply disconnect and check the crankcase oil level.
Add oil only if necessary to bring the oil into view in the
sight glass. If oil is added, run the compressor for an addi­tional 10 minutes, then stop and check oil level. If the level
remains low, check the piping system for proper design for
oil return; also, check the system for leaks.

If the initial check shows too much oil (too high in the
sight glass) remove oil to proper level. See Preliminary Oil
Charge, this page, for proper procedure for adding and
removing oil. See Fig. 9.

When the above checks are complete, repeat the proce­dure with the unit operating at minimum load conditions.

Unload the compressor by turning the control set point
adjustment nut counterclockwiseuntiltheadjustmentnutstops.
The unloader is now at 0 psig (0 kPag) set point. If electric
actuated unloaders are installed, energize the solenoid to un­load the compressor.

Return unloader to original setting after checks are
complete.

Start Unit — The field disconnect is closed, the fan cir-

cuit breaker is closed, and the space thermostat is set above
ambient so that there is no demand for cooling. Only the
crankcase heater will be energized.

Next, close the compressor circuit breaker and then reset
space thermostat below ambient so that a call for cooling is
ensured. If compressor does not start, set thermostat lower.

NOTE: Do not use circuit breaker to start and stop the com­pressor except in an emergency.

After starting, there is a delay of at least 3 seconds before
compressor starts.

38AKS024 38AKS013,014,016

(06E COMPRESSOR) (06D COMPRESSOR)

Fig. 9 — Operating Oil Levels

Final Checks — Ensure all safety controls are operat-

ing, control panel covers are on, and the service panels are
in place.

13

14

Fig. 10 — 38AKS013 and 38AKS024 Charging Chart

15

Fig. 11 — 38AKS014 Charging Chart

16

Fig. 12 — 38AKS016 Charging Chart

OPERATING SEQUENCE

Cooling—

mostat closes, the timer starts. After approximately
3 seconds, the timer expires, energizing the compressor and
fan motor no. 1. When the liquid pressure builds to approxi­mately 257 psig (1772 kPa), fan motor no. 2 is energized.

On demand for additional cooling capacity, the second stage
(TC2) of the cooling thermostat closes, energizing a field­supplied liquid line solenoid (LLS) valve, whichopens.This
increases the suction pressure, causing the compressor to
operate at higher capacity.

When fan switch is set at AUTO,theindoor unit fan cycles
with the compressor. When the switch is set at ON, the
indoor unit fan runs continuously.

At shutdown, the Time Guardt II timer prevents the com­pressor from restarting for approximately 5 minutes.

When installed, a field-supplied solenoid valve (wired in
parallel with the compressor contactor coil), shuts off the liq­uid line to prevent refrigerant migration back to the com­pressor during the off cycle.

When the first stage (TC1) of the cooling ther-

Heating— The heating thermostat (TH) energizes a field-

supplied relay which operates heating controls and ener­gizes the indoorunitrelay. When the fan switch issetatAUTO,
the indoor unit fan cycles with the heating control. The
indoor unit fan runs continuously when the fan switch is set
at ON.

Causes of complete unit shutdown are: interruption of sup­plied power, open compressor internal protector (IP), open
control circuit breaker,oranopenhigh-orlow-pressuresafety
switch.

PRESSURE DIFFERENTIAL (difference between cylinder
load and unload points) is adjustable from 6 to 22 psig
(41.4 to 152 kPag). To adjust, turn pressure differential ad­justment screw (Fig. 13) counterclockwise to its back stop
position. In this position, differential is 6 psig (41.4 kPag).
Next, turn adjustment clockwise to desired pressure differ­ential setting. Every full turn clockwise increases differen­tial by 1.5 psig (10.3 kPag).

Head Pressure Control — Fan cycling is a standard

feature. The no. 2 fan cycles in response to changes in liquid
pressure. The switch cycles the fan off at 160 ± 10 psig
(1103 ± 69 kPa) as pressure decreases, and cycles it back on
at 255 ± 10 psig (1758 ± 69 kPa).

Fan Cycling — Head pressure control is accomplished

by cycling the fans. The no. 2 fan responds to liquid line
pressure, cycling on at approximately 255 psig (1758 kPa)
and off at approximately 160 psig (1103 kPa).

WinterStart Control (If Installed) — When thecom-

pressor starts, the control’s bypass timer contacts close for
150 seconds, thereby bypassing the low-pressure switch dur­ing start-up. After 150 seconds, the bypass timer contacts
open and the low-pressure switch is restored to the safety
circuit.

SERVICE

Capacity Control —

unloader controls 2 cylinders and provides capacity control.
Unloaders are factory set (see Tables 1A-1D), but can be
field adjusted as described in the 2 following sections.

CONTROL SET POINT (cylinder load point) is adjustable
from 0 to 85 psig (586 kPa). To adjust, turn control set point
adjustment nut (Fig. 13) clockwise to its bottom stop. In this
position, set point is 85 psig (586 kPa). Next, turn adjust­ment counterclockwise to desired control set point. Every
full turn counterclockwise decreases set point by 7.5 psig
(51.7 kPa).

A suction pressure-actuated

Fig. 13 — Compressor Capacity Control Unloader

Time Guard II Circuit — Circuit prevents short-

cycling by providing a delay of approximately 5 minutes
before restarting compressor after shutdown from safety
device action.

On start-up, the Time Guard II timer causes a delay of

approximately 3 seconds after thermostat closes.

On compressor shutdown, the timer recycles for approxi­mately 5 minutes. During this time, the compressor cannot
restart.

Refer to Fig. 14 and to label diagram on unit.

Fig. 14 — Timer Sequence Chart

17

Winter Start Control (If Required) — Install Ac-

cessory Package 38AE900021.

Crankcase Heater — The heater prevents refrigerant

migration and compressor oil dilution during shutdown when­ever compressor is not operating. It is wired to cycle with
the compressor; the heater is off when compressor is run­ning, and on when compressor is off.

Both compressor service valves must be closed whenever
the crankcase heater is deenergized for more than 6 hours.
The crankcase heater is operable as long as the control cir­cuit is energized.

Compressor Protection

CIRCUIT BREAKER — Calibrated trip manual reset, am­bient compensated, magnetic breaker protects against motor
overload and locked rotor conditions.

COMPRESSOR OVER TEMPERATUREPROTECTION(IP)
— A thermostat installed on compressor motor winding
reacts to excessively high winding temperatures and shuts
off the compressor.

TIME GUARDt II CONTROL — Control prevents com­pressor from short cycling. See Operating Sequence.

CRANKCASE HEATER — Heater minimizes absorptionof
liquid refrigerant by oil in crankcase during brief or ex­tended shutdown periods. The control circuit is maintained
if compressor fan motor circuit breakers are turned off. The
main disconnect must be on to energize crankcase heater.

IMPORTANT: Never open any switch or disconnect
that energizes the crankcase heater unless unit is being
serviced or is to be shut down for a prolonged period.
After a prolonged shutdown on a service job, energize
the crankcase heater for 24 hours before starting the
compressor.

High-Pressure Switches — Switches have fixed,

nonadjustable settings. Switches are mounted on the
compressors.

Low-Pressure Switches — Switches have fixed,

nonadjustable settings. Switches are mounted on the
compressors.

TO CHECK — Slowly close liquid shutoff valve and allow
compressor to pump down. Do not allow compressor
pump-down below 2 psig (13.8 kPa). Compressor should shut
down when suction pressure drops to cutout pressure in
Tables 1A-1D, and should restart when pressure builds up to
cut-in pressure shown.

Outdoor Fans — Each fan is supported by a formed-

wire mount bolted to the fan deck and covered with a wire
guard. The exposed end of the motor shaft is covered with
a rubber boot. In case a fan motor must be repaired or re­placed, be sure the rubber boot is put back on when the fan
is reinstalled and be sure the fan guard is in place before
starting the unit. Figure 15 shows the proper position of the
mounted fan. Fan motors have permanently lubricated
bearings.

Lubrication

F ANMOTORS have sealed bearings. No provisions are made
for lubrication.

COMPRESSOR has its own oil supply. Loss of oil due to a
leak in the system should be the only reason for adding oil
after the system has been in operation. See Preliminary Oil
Charge section.

CleaningCoils— Thecoilscanbecleanedwithavacuum

cleaner, washed out with low velocity water, blown out with
low-pressure compressed air, or brushed (do not use wire
brush). Fan motors are drip-proof but not waterproof. Do
NOT use acid cleaners.

Clean outdoor coil annually or as required by location or
outdoor air conditions. Inspect coil monthly, and clean as
required. Fins are not continuous through coil sections; dirt
and debris may pass through first section, become trapped
between the 2 rows of fins (38AKS013) or 3 rows of fins
(38AKS014-024) and restrict outdoor airflow. Use a flash­light to determine if dirt or debris has collected between coil
sections. Clean coil as follows:

1. Turn off unit power.

2. Remove screws holding rear corner posts and top

cover in place. Pivot top cover up 12 to 18 in. (305 to
457 mm) and support with a rigid support. See Fig. 16.

3. Remove clips securing tube sheets together at the return

bend end of the coil. Carefully spread the ends of the coil
rows apart by moving the outer sections. See Fig. 17.

4. Using a water hose, orothersuitableequipment,flushdown

between the sections of coil to remove dirt and debris.

5. Clean the remaining surfaces in the normal manner.

6. Reposition outer coil sections.

7. Reinstall clips which secure tube sheets.

8. Replace top cover and rear corner posts.

18

Fig. 15 — Outdoor Fan

Fig. 17 — Coil Cleaning (Typical)

Fig. 16 — Pivot and Support Top Cover

19

TROUBLESHOOTING

PROBLEM SOLUTION

COMPRESSOR DOES NOT RUN

Contactor Open

1. Power off. 1. Restore power.

2. Fuses blown in field power circuit. 2. After finding cause and correcting, replace with correct size fuse.

3. No control power. 3. Check control circuit breaker; reset if tripped or replace if defective.

4. Thermostat circuit open. 4. Check thermostat setting.

5. Time GuardT II device not operating. 5. Check Time Guard II devices.

6. Compressor circuit breaker tripped. 6. Check for excessive compressor current draw. Reset breaker;

7. Safety device lock-out circuit active. 7. Reset lock-out circuit at thermostat or circuit breaker.

8. Low-pressure switch open. 8. Check for refrigerant undercharge, obstruction of indoor airflow, or

9. High-pressure switch open. 9. Check for refrigerant overcharge, obstruction of outdoor airflow, air in

10. Compressor overtemperature switch open. 10. Check for open condition. Allow for reset. Replace if defective.

11. Loose electrical connections. 11. Tighten all connections.

12. Compressor stuck. 12. See compressor service literature.
Contactor Closed

1. Compressor leads loose. 1. Check connections.

2. Motor windings open. 2. See compressor service literature.

3. Single phasing. 3. Check for blown fuse. Check for loose connection at compressor terminal.

COMPRESSOR STOPS ON HIGH-PRESSURE SWITCH

Outdoor Fan On

1. High-pressure switch faulty.

2. Reversed fan rotation. 2. Confirm rotation, correct if necessary.

3. Airflow restricted. 3. Remove obstruction.

4. Air recirculating. 4. Clear airflow area.

5. Noncondensables in system. 5. Recover refrigerant and recharge as required.

6. Refrigerant overcharge. 6. Recover refrigerant as required.

7. Line voltage incorrect. 7. Consult power company.

8. Refrigerant system restrictions. 8. Check or replace filter drier, expansion valve, etc. Check that compressor
Outdoor Fan Off

1. Fan slips on shaft. 1. Tighten fan hub setscrews.

2. Motor not running. 2. Check power and capacitor.

3. Motor bearings stuck. 3. Replace bearings.

4. Motor overload open. 4. Check overload rating. Check for fan blade obstruction.

5. Motor burned out. 5. Replace motor.

COMPRESSOR CYCLES ON LOW-PRESSURE SWITCH

Indoor-Air Fan Running

1. Compressor suction service valve partially closed.

2. Liquid line solenoid valve(s) fails to open. 2. Check liquid line solenoid valve(s) for proper operation. Replace if

3. Filter drier plugged. 3. Replace filter drier.

4. Expansion valve power head defective. 4. Replace power head.

5. Low refrigerant charge. 5. Add charge. Check low-pressure switch setting.

replace if defective.

whether compressor suction shutoff valve is fully open. Make sure liquid
line solenoid valve(s) is open.

system, or whether compressor discharge valve is fully open. Be sure
outdoor fans are operating correctly.

1. Replace switch.

discharge service valve is fully open.

1. Open valve fully.
necessary.

20

TROUBLESHOOTING (cont)

PROBLEM SOLUTION

COMPRESSOR CYCLES ON LOW-PRESSURE SWITCH (cont)

Airflow Restricted

1. Coil iced up. 1. Check refrigerant charge.

2. Coil dirty. 2. Clean coil fins.

3. Air filters dirty. 3. Clean or replace filters.

4. Dampers closed. 4. Check damper operation and position.
Indoor-Air Fan Stopped

1. Electrical connections loose.

2. Fan relay defective. 2. Replace relay.

3. Motor overload open. 3. Power supply.

4. Motor defective. 4. Replace motor.

5. Fan belt broken or slipping. 5. Replace or tighten belt.

COMPRESSOR RUNNING BUT COOLING INSUFFICIENT

Suction Pressure Low

1. Refrigerant charge low.

2. Head pressure low. 2. Check refrigerant charge.

3. Air filters dirty. 3. Clean or replace filters.

4. Expansion valve power head defective. 4. Replace power head.

5. Indoor coil partially iced. 5. Check low-pressure setting.

6. Indoor airflow restricted. 6. Remove obstruction.
Suction Pressure High

1. Unloaders not functioning. 1. Check unloader adjustments.

2. Compressor valve defective. 2. See compressor service literature.

3. Heat load excessive. 3. Check for open doors or windows in vicinity of fan coil.

UNIT OPERATES TOO LONG OR CONTINUOUSLY

1. Low refrigerant charge. 1. Add refrigerant.

2. Control contacts fused. 2. Replace control.

3. Air in system. 3. Purge and evacuate system.

4. Partially plugged expansion valve or filter drier. 4. Clean or replace.

SYSTEM IS NOISY

1. Piping vibration. 1. Support piping as required.

2. Compressor noisy. 2. Check valve plates for valve noise. Replace compressor if

COMPRESSOR LOSES OIL

1. Leak in system. 1. Repair leak.

2. Crankcase heaters not energized during shutdown. 2. Check wiring and relays. Check heater and replace if

3. Improper interconnecting piping design. 3. Check piping for oil return. Replace if necessary.

FROSTED SUCTION LINE

Expansion valve admitting excess refrigerant. Adjust expansion valve.

HOT LIQUID LINE

1. Shortage of refrigerant due to leak. 1. Repair leak and recharge.

2. Expansion valve opens too wide. 2. Adjust expansion valve.

FROSTED LIQUID LINE

1. Restricted filter drier. 1. Remove restriction or replace.

2. Liquid line solenoid valve partially closed. 2. Replace valve.

COMPRESSOR WILL NOT UNLOAD

1. Defective unloader. 1. Replace unloader.

2. Defective capacity control solenoid valve (if used). 2. Replace valve.

3. Miswired capacity control liquid line solenoid (if used). 3. Rewire correctly.

4. Weak, broken, or wrong valve body spring. 4. Replace spring.

COMPRESSOR WILL NOT LOAD

1. Miswired capacity control liquid line solenoid (if used). 1. Rewire correctly.

2. Defective capacity control solenoid valve (if used). 2. Replace valve.

3. Plugged strainer (high side). 3. Clean or replace strainer.

4. Stuck or damaged unloader piston or piston ring(s). 4. Clean or replace the necessary parts.

1. Tighten all connections.

1. Add refrigerant.

Check outdoor-air fan thermostat settings.

Check unloader setting.

bearings are worn.

defective.

21

Copyright 1998 Carrier Corporation

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book 1 4
Tab 3a 2a

PC 111 Catalog No. 563-701 Printed in U.S.A. Form 38AKS-3SI Pg 22 9-98 Replaces: 38AKS-2SI

START-UP CHECKLIST

A. Preliminary Information

OUTDOOR: MODEL NO. SERIAL NO.
INDOOR: AIR HANDLER MANUFACTURER

MODEL NO. SERIAL NO.

ADDITIONAL ACCESSORIES

B. Pre-Start-Up

OUTDOOR UNIT

IS THERE ANY SHIPPING DAMAGE?
IF SO, WHERE:

WILL THIS DAMAGE PREVENT UNIT START-UP? (Y/N)
CHECK POWER SUPPLY. DOES IT AGREE WITH UNIT? (Y/N)

HAS THE GROUND WIRE BEEN CONNECTED? (Y/N)
HAS THE CIRCUIT PROTECTION BEEN SIZED AND INSTALLED PROPERLY? (Y/N)
ARE THE POWER WIRES TO THE UNIT SIZED AND INSTALLED PROPERLY? (Y/N)
HAVE COMPRESSOR HOLDDOWN BOLTS BEEN LOOSENED (Snubber washers are snug, but not tight)?

(Y/N)

(Y/N)

CONTROLS

ARE THERMOSTAT AND INDOOR FAN CONTROL WIRING

CONNECTIONS MADE AND CHECKED? (Y/N)
ARE ALL WIRING TERMINALS (including main power supply) TIGHT? (Y/N)
HAS CRANKCASE HEATER BEEN ENERGIZED FOR 24 HOURS? (Y/N)

INDOOR UNIT

HAS WATER BEEN PLACED IN DRAIN PAN TO CONFIRM PROPER DRAINAGE? (Y/N)
ARE PROPER AIR FILTERS IN PLACE? (Y/N)
HAVE FAN AND MOTOR PULLEYS BEEN CHECKED FOR PROPER ALIGNMENT? (Y/N)
DO THE FAN BELTS HAVE PROPER TENSION? (Y/N)
HAS CORRECT FAN ROTATION BEEN CONFIRMED? (Y/N)

PIPING

ARE LIQUID LINE SOLENOID VALVES LOCATED AT THE INDOOR COILS AS REQUIRED? (Y/N)
HAVE LEAK CHECKS BEEN MADE AT COMPRESSOR, OUTDOOR AND INDOOR COILS,

TXVs (Thermostatic Expansion Valves), SOLENOID VALVES, FILTER DRIERS, AND FUSIBLE PLUGS

WITH A LEAK DETECTOR? (Y/N)
LOCATE, REPAIR, AND REPORT ANY LEAKS.
HAVEALL COMPRESSOR SERVICE VALVES BEEN FULLY OPENED (BACKSEATED)? (Y/N)
HAVE LIQUID LINE SERVICE VALVES BEEN OPENED? (Y/N)
IS THE OIL LEVEL IN EACH COMPRESSOR CRANKCASE VISIBLE IN THE COMPRESSOR SIGHT GLASSES?

(Y/N)

CHECK VOLTAGE IMBALANCE

LINE-TO-LINE VOLTS: AB
(AB + AC + BC)/3 = AVERAGE VOLTAGE =
MAXIMUM DEVIATION FROM AVERAGE VOLTAGE =
VOLTAGE IMBALANCE = 100 X (MAX DEVIATION)/(AVERAGE VOLTAGE) =
IF OVER 2% VOLTAGE IMBALANCE, DO NOT ATTEMPT TO START SYSTEM!

CALL LOCAL POWER COMPANY FOR ASSISTANCE.

VAC VBC V

V

V

CL-1

%

C. Start-Up

CHECK INDOOR UNIT FAN SPEED AND RECORD.
CHECK OUTDOOR UNIT FAN SPEED AND RECORD.
AFTER AT LEAST 10 MINUTES RUNNING TIME, RECORD THE FOLLOWING MEASUREMENTS:

OIL PRESSURE
SUCTION PRESSURE
SUCTION LINE TEMP
DISCHARGE PRESSURE
DISCHARGE LINE TEMP
ENTERING OUTDOOR UNIT AIR TEMP
LEAVING OUTDOOR UNIT AIR TEMP
INDOOR UNIT ENTERING-AIR DB (dry bulb) TEMP
INDOOR UNIT ENTERING-AIR WB (wet bulb) TEMP
INDOOR UNIT LEAVING-AIR DB TEMP

INDOOR UNIT LEAVING-AIR WB TEMP
COMPRESSOR AMPS (L1/L2/L3) / /
CHECK THE COMPRESSOR OIL LEVEL SIGHT GLASSES; ARE THE SIGHT GLASSES SHOWING

OIL LEVEL IN VIEW? (Y/N)

NOTES:

Copyright 1998 Carrier Corporation

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book 1 4
Tab 3a 2a

PC 111 Catalog No. 563-701 Printed in U.S.A. Form 38AKS-3SI CL-2 9-98 Replaces: 38AKS-2SI

CUT ALONG DOTTED LINE CUT ALONG DOTTED LINE

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