REFRIGERANT LEAK TESTS
Testing for Leaks:
In event it is suspected that there is a leak in the system, it will be necessary to check the entire system. This means all
tubing connections, valves, receiver, condenser, evaporator, compressor.
The method of testing for leaks in two fold, depending on whether or not the leak occurs on the highside or on the lowside.
The lowside refers to that part of the system constituting the evaporator, suction line, and crankcase up to the intake valve
located in the valve plate.
The highside refers to that part of the system extending from the cylinder head, condenser, receiver tank and liquid line up
to the expansion valve.
It is evident that before testing for leaks on the lowside, it is necessary to build up a pressure on the lowside. This is done
by attaching the pressure gauge at the suction service valve, shutting off the unit, adjusting the expansion valve to a wide
open position until sufficient pressure (at least 70 pounds) is built up in the lowside. If the system has been allowed to
cool down, 45 to 50 pounds is all that can be obtained.
Soap Test Method:
Place a small piece of shaving soap, or any good soap that will make a heavy lather in a cup; add water to the soap just
as you would prepare a lather for shaving; apply the lather with a small brush completely around and over every joint to be
tested; hold a light from a torch flashlight in such a manner that the entire joint can be inspected; if there is any leaks, it
will be indicated by a formation of small bubbles. (in the event of a leak, repair the leak and repeat the test).
Oil Test Method:
In the event that soap is not available, oil may be substituted for the lather; apply the oil with a small brush, completely
around the and over every joint to be tested; If there is any leak, it will be indicated by a formation of small bubbles; where
the oil method is used, a heavy grade of oil should be applied to all joints as a light grade will run off before the test can be
made. Wipe all traces of oil from the joints after the test had been completed.
