Gree GWC09AA, Installation And Service Manual

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GREE Service Manual GWC09AA / K5NNA6A Page 87
Leak Check (Bubble Test) with a weak soapy water solution
Leak Testing with the use of “Weak Soap Solution with Water” only is not a reli-
able comprehensive Leak Testing activity but in combination with other leak
testing methods it is a simple, sensitive technology. Specifically, the bubble test
method would only be unsuitable if the system or section being tested is operat-
ing in a vacuum.
A soapy water solution can be used when you know the approximate area
where a leak may exist and sufficient refrigerant pressure in the system is avail-
able. In addition it may be noticed that there is oil covering the surface of the
suspected leak-spot. Previously e.g. an electronic leak detector has indicated a
leak exists in a particular area of the hermetically sealed system. Mechanical
connections will be the first choice to look for leaks in general.
Many different types of soap solutions are available on the market. Some tech-
nicians create their own soapy water solution. Some purchase bubble-test
bottles and may have a pen-brush to apply the solution to the suspected point of
leakage. A small brush is the best (cleanest) way to work with soapy water on
RAC systems.
Some brands may provide “weak soap water solutions” in a spray bottle to cover
quick “large” areas of pipe work or components for leak finding. Some soap
solutions consist of an antifreeze mixture to avoid frosting of the solution on sys-
tem parts. The advantage of most commercially produced solution for bubble
test is that they have a lower density to make them even more sensitive to very
tiny leaks.
Hints for the use of weak soap solutions:
1. If the system does not contain sufficient pressure for leak detection, the re-
frigerant can be recovered from the system and the system re-pressurised
with OFDN to increase the pressure.
2. Probably in some cases the escaping Nitrogen is audible and indicates the
leakage location.
3. Do not pressurise the system or component to be checked, more than the
manufactures leak testing standards. This pressure is usually stated on the
data plate as “Maximum Allowable Pressure”.
4. In most cases for the purpose of leak testing, a safe pressure is usually
about 10 bar (150 psig).
Example of “Bubble Test” application and a commercially provided Leak Check
fluid with Pin Brush