How to Find Refrigerant Coil Leaks
- 1). Check to see if you see ice along the lines that point to the outside of the unit. This is a clear indicator that your air-conditioning coil is icing up, potentially due to a refrigerant leak.
- 2). Examine the shrader valves to see if they are leaking refrigerant. The valves resemble the valves in your car's tires, and can be easily fixed if they are the source of the leak.
- 3). Look out for rust holes in your heat pump's accumulators, if your unit has them. The accumulators are made of steel, and if they haven't been previously sprayed with a rust-prevention agent, in time they will begin to spring leaks. Also, closely examine the unit's filter dryers, which can also rust over, leading to leaks.
- 4). Try to spot holes on the surface of the capillary tubes that run on the inside evaporator, or on the outside head pump condensing unit if your air-conditioner has a heat pump. This requires disassembling the entire unit, so if you don't feel comfortable doing that, wait for the HVAC technician to arrive. Also look for leaks on your unit's flare connections.
- 5). Check the indoor and outdoor air-conditioning coils, as well as the heat pump coils, for leaks. These leaks generally spring up at the copper U-tubes at the end of the coil, near the sheet metal tube sheet. The tube sheet over time rubs against the coils, creating leaks.
- 6). Inspect the line set that stretches from the condenser to the evaporator coil for any damage. The line sets often run inside walls and ceilings.
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