Carrier 38AE012 Pre-Start-Up, Before Starting Unit ensure the following, Ð Charging Data R-22

Models: 38AE014 38AE016 38AE012

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PRE-START-UP

PRE-START-UP

Evacuate and Dehydrate the entire refrigerant sys- tem by either of the methods described in Carrier Standard Service Techniques Manual, Chapter 1.

Leak Test the entire refrigerant system by the pres- sure method described in Carrier Standard Service Tech- niques Manual, Chapter 1. Use R-22 at approximately 25 psig (172.4 kPa) backed up with an inert gas to a total pressure not to exceed 245 psig (1689 kPa).

Turn on Crankcase Heaters for 24 hours before start- ing the unit to be sure all the refrigerant is out of the oil. To energize the crankcase heaters, proceed as follows.

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

2.Close the ®eld disconnect.

3.Turn the fan circuit breaker on. Leave the compressor cir- cuit breakers off. The crankcase heaters are now energized.

Add Preliminary Charge to the refrigerant system ac- cordingly to Carrier Standard Service Techniques Manual, Chapter 1. By the liquid charging method and charging by weight procedure, charge the units with approximately the amounts of R-22 refrigerant shown in Table 6.

Table 6 Ð Charging Data (R-22)

 

REFRIGERANT CHARGE - lb (kg)

CONDENSING

UNIT

Required Charge

Outdoor Unit

TEMP

 

Above Clear

Total Charge

DURING

 

Sight Glass

(Approx)

CHARGING - F (C)

38AE012

3.0 (1.4)

22 (10)

125 (51.7)

38AE014

4.8 (2.2)

23 (10.5)

123 (50.6)

38AE016

3.4 (1.5)

23 (10.5)

130 (54.4)

38AKS024

3.4 (1.5)

28 (12.7)

131 (54.8)

 

 

 

 

Before Starting Unit ensure the following:

1.Compressor oil level must be at least within sight in the compressor sight glass. Add oil if necessary (see Tables 1A-1D and Oil Charge section).

2.Compressor holddown bolts must be snug, but not tight. Refer to Compressor Mounting section and tag on com- pressor foot.

3.All internal wiring connections must be tight; all barriers and covers must be in place.

4.Electrical power source must agree with unit nameplate rating.

5.All service valves must be open.

6.Crankcase heater must be ®rmly locked into the com- pressor crankcase.

START-UP

To Start Unit Ð Set thermostat set point below the space temperature. After starting unit, there is a delay of at least 3 seconds before compressor starts.

Oil Charge (see Tables 1A-1D) ÐAllow unit to run for about 20 minutes. Stop unit and check compressor oil level at sight glass. Add oil if necessary to bring oil to the correct level shown in Fig. 8. Use only Carrier-approved compres- sor oil. Approved oils are:

Witco Chemical Corp. . . . . . . . . . . . . . . . . Suniso 3GS Texaco, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . WF32 Petroleum Specialties Co. . . . . . . . . . . . . . . . Cryol 150

Do not reuse drained oil or use any oil that has been ex- posed to atmosphere. Procedures for adding or removing oil are given in Carrier Standard Service Techniques Manual, Chapter 1, Refrigerants.

If oil is added, run unit for additional 10 minutes. Stop unit and check oil level. If level is still low, add oil only after determining that piping system is designed for proper oil re- turn and that the system is not leaking oil.

38AKS024

38AE012,014,016

(06E COMPRESSOR)

(06D COMPRESSOR)

Fig. 8 Ð Operating Oil Levels

Refrigerant Charge Ð Actual start-up should be done only under supervision of a quali®ed refrigeration me- chanic. Refer to charging charts.

See Fig. 9-11 for the particular unit being charged. Mea- sure pressure at the liquid line service valve, being sure a Schrader depressor is used if required. Also, measure liquid line temperature as close to the liquid service valve as pos- sible. Add or reduce charge until the pressure and tempera- ture conditions of the charging charge curve are met. If liq- uid pressure and temperature point falls above curve, add charge. If liquid pressure and temperature point falls below curve, reduce the charge until the conditions match the curve.

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

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Carrier 38AE012 Pre-Start-Up, Before Starting Unit ensure the following, Ð Charging Data R-22, Ð Operating Oil Levels