Bryant R-22 service manual Compressor Removal and Replacement, System Clean-Up After Burnout

Compressor Removal and Replacement

Once it is determined that compressor has failed and the reason established, compressor must be replaced.

!CAUTION

PERSONAL INJURY HAZARD

Failure to follow this caution may result in personal injury.

Turn off all power to unit before proceeding. Wear safety glasses, protective clothing, and gloves when handling refrigerant. Acids formed as a result of motor burnout can cause burns.

!CAUTION

PERSONAL INJURY HAZARD

Failure to follow this caution may result in personal injury.

Wear safety glasses, protective clothing, and gloves when handling refrigerant and when using brazing torch..

1.Shut off all power to unit.

2.Remove and recover all refrigerant from system until pressure gauges read 0 psi. Use all service ports. Never open a system under a vacuum to atmosphere. Break vacuum with dry nitrogen holding charge first. Do not exceed 5 psig.

3.Disconnect electrical leads from compressor. Disconnect or remove crankcase heater and remove compressor hold-down bolts.

4.Cut compressor from system with tubing cutter. Do not use brazing torch for compressor removal. Oil vapor may ignite when compressor is disconnected.

5.Scratch matching marks on stubs in old compressor. Make corresponding marks on replacement compressor.

6.Use torch to remove stubs from old compressor and to reinstall them in replacement compressor.

7.Use copper couplings to tie compressor back into system.

8.Replace filter drier, evacuate system, recharge, and check for normal system operation.

!CAUTION

UNIT DAMAGE HAZARD

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

Do not leave system open to atmosphere. Compressor oil is highly susceptible to moisture absorption.

System Clean-Up After Burnout

Some compressor electrical failures can cause motor to burn. When this occurs, by-products of burn, which include sludge, carbon, and acids, contaminate system. Test the oil for acidity using POE oil acid test to determine burnout severity. If burnout is severe enough, system must be cleaned before replacement compressor is installed. The 2 types of motor burnout are classified as mild or severe.

In mild burnout, there is little or no detectable odor. Compressor oil is clear or slightly discolored. An acid test of compressor oil will be negative. This type of failure is treated the same as mechanical failure. Liquid-line strainer should be removed and liquid-line filter drier replaced.

In a severe burnout, there is a strong, pungent, rotten egg odor. Compressor oil is very dark. Evidence of burning may be present in tubing connected to compressor. An acid test of compressor oil will be positive. Follow these additional steps:

1.TXV must be cleaned or replaced.

2.Drain any trapped oil from accumulator if used.

3.Remove and discard liquid-line strainer and filter drier.

4.After system is reassembled, install liquid and suction-line Puronr filter driers.

NOTE: On heat pumps, install suction line drier between compressor and accumulator.

5.Operate system for 10 hr. Monitor pressure drop across drier. If pressure drop exceeds 3 psig replace suction-line and liquid-line filter driers. Be sure to purge system with dry nitrogen when replacing filter driers. If suction line driers must be replaced, retest pressure drop after additional 10 hours (run time). Continue to monitor pressure drop across suction line filter drier. After 10 hr of run time, remove suction-line filter drier and replace liquid-line filter drier. Never leave suction-line filter drier in system longer than 72 hr (run time).

6.Charge system. (See unit information plate.)

!CAUTION

UNIT DAMAGE HAZARD

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

Only suction line filter driers should be used for refrigerant and oil clean up. Use of non-approved products could limit system life and void unit warranty.

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