How to Monitor a Refrigerant Leak

Turn on the leak detector and let it warm up approximately 10 seconds. Run the leak detector wand over the unit and watch for immediate results. It detects the slightest bit of refrigerant in the vicinity with beeps and flashes. If it does not signal, then there is not a leak and nothing further needs to be done on this particular unit. If it does beep, it means that more work must be done to detect the seriousness of the leak.

Shut the unit off and plug the pressure gauges into the unit cooling system, with the high pressure red gauge to the high pressure red valve, the low pressure blue gauge to the low pressure blue valve and the yellow to the yellow refrigerant. Different refrigerants require different types of fittings on the gauges, so be sure you use the correct connectors.

Turn the unit back on and after 15 minutes read the pressure gauges. Measure the interior temperature of the unit in several places. The appliance should have a chart inside the frame that gives you the amount of refrigerant still within the system based upon the readings from the pressure gauges and the interior temperature of the unit. Both temperature and pressure fluctuate from other variables, but reading them together allows a precise placement on the chart of the amount of refrigeration available.

Compare this existing available amount with the amount the chart shows should be in the system to find the percentage of refrigerant remaining. If the appliance has lost more than 30 percent of the refrigerant, then by law, any leak must be fixed. If it is less than 30 percent, then more refrigerant may be added and nothing further done. If the leak is sufficiently large, though, it will soon require another trip to fill more refrigerant. It might be more cost-effective to fix it at this moment.