Dear Angie: I have an old heat pump air conditioner with R-22 refrigerant that leaks out periodically. I’ve heard of contractors using a leak sealant to correct this problem. Are sealants effective?
Also, I’ve seen some newer models claim to be 30 percent more efficient compared to my 15-year-old unit. Is this true?
I’ve also read that the R-410A refrigerant for newer units has a much smaller molecule size, which makes it leak out faster. Is this true and if so, are the units built better to compensate for this? – Al B., Bardstown, Kentucky.
Dear Al: Some heating and cooling contractors do offer a refrigerant leak sealant, however, many do not. Sealers can sometimes be effective in addressing small leaks, but they are considered a short-term fix, rather than a long-term solution. Many contractors won’t use these sealers, because they can create blocked passages and openings within the system, which could actually do more harm than good.
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All that said, you really need to examine why your air conditioning system is losing coolant. A properly working system should never leak refrigerant. If your system is losing refrigerant, there's a mechanical problem that you need to address. Refrigerant that leaks into the atmosphere is an environmental hazard and as the owner, you are responsible for ensuring your A/C unit is not leaking.
A common cause of leaking refrigerant is due to a leak in the evaporator coil or outdoor condenser coil. This can only be fixed by replacing the part. For a 15-year-old system, that’s probably not an investment worth making. The unit is likely less efficient than a newer unit; and the R-22 refrigerant you’ll need to replace is increasing in cost as it is being phased out of production and replaced with more environmentally friendly R-410A.
MORE: What is a Fair Price for R-22?