Carrier 024-036 Service Manual Download Page 24

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

A95422

Fig. 25 – Electronic Leak Detection

Assuming that a system is pressurized with either all refrigerant or a

mixture of nitrogen and refrigerant, leaks in the system can be found

with an electronic leak detector that is capable of detecting specific

refrigerants.
If system has been operating for some time, first check for a leak

visually. Since refrigerant carries a small quantity of oil, traces of oil at

any joint or connection is an indication that refrigerant is leaking at that

point.
A simple and inexpensive method of testing for leaks is to use soap

bubbles. (See

Fig. 26

.) Any solution of water and soap may be used.

Soap solution is applied to all joints and connections in system. A small

pinhole leak is located by tracing bubbles in soap solution around leak. If

the leak is very small, several minutes may pass before a bubble will

form. Popular commercial leak detection solutions give better,

longer-lasting bubbles and more accurate results than plain soapy water.

The bubble solution must be removed from the tubing and fittings after

checking for leaks as some solutions may corrode the metal.

A95423

Fig. 26 – Bubble Leak Detection

You may use an electronic leak detector designed for specific refrigerant

to check for leaks. (See

Fig. 25

.) This unquestionably is the most

efficient and easiest method for checking leaks. There are various types

of electronic leak detectors. Check with manufacturer of equipment for

suitability. Generally speaking, they are portable, lightweight, and

consist of a box with several switches and a probe or sniffer. Detector is

turned on and probe is passed around all fittings and connections in

system. Leak is detected by either the movement of a pointer on detector

dial, a buzzing sound, or a light.
In all instances when a leak is found, system charge must be recovered

and leak repaired before final charging and operation. After leak testing

or leak is repaired, replace liquid line filter drier, evacuate system, and

recharge with correct refrigerant quantity.

Coil Removal

Coils are easy to remove if required for compressor removal, or to

replace coil.

1. Shut off all power to unit.
2. Recover refrigerant from system through high flow service valves.
3. Break vacuum with nitrogen.
4. Remove top cover. (See Access Compressor or other internal

cabinet component,

Fig. 6

Fig. 8

5. Remove screws in coil panels.

6. Use midget tubing cutter to cut liquid and vapor lines at both sides

of coil. Cut in convenient location for easy reassembly with copper

slip couplings.

7. Lift coil vertically from basepan and carefully place aside.
8. Reverse procedure to reinstall coil.
9. Replace filter drier, evacuate system, recharge, and check for

normal systems operation.

Compressor Removal and Replacement

Once it is determined that compressor has failed and the reason

established, compressor must be replaced.

1. Shut off all power to unit.
2. Remove and recover all refrigerant from system until pressure

gauges read 0 psig. 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