How much should a coil cleaning for central AC cost? Details?
Also, how often should this be done?
And how should it be gone about? Same technique if it's done yearly or if you wait till they get really dirty (say three-four years)?
I think my coils my have some issues. :( The former owners of this home had them replaced about 4 years ago.
My house is cooling for crud. It does cool but VERY, VERY slowly. Condenser went a week ago. Was replaced. Now this. Probably wasn't blowing/coolling up to snuff even before the condenser went so I'm not sure there's a correlation with the condenser unit prob. Obviously not sure though. I didn't notice really until it went completely.
Answers:
I don't like attic installations for air handlers. They're really not designed for that application, and invariably it leads to problems.
The evaporator coil cleaning, to be done properly, involves pumping down and capturing the refrigerant, cutting the lines to the coil, removing it from the attic and cleaning it on the ground. An alkaline (not acid) based cleaner should be used, and rinsed with a reasonably high-powered hose until you can see daylight through the fins when you hold in up to the sunlight. It may require several attempts to get the coil really clean. An "in-place" cleaning is totally unacceptable, and can do more harm than good.
The cost for a cleaning, because of the difficulty level, is not far from the cost of a new coil. Expect to pay in the neighborhood of $400.00. A new coil will run $750 for a 3-4 ton unit. it sounds like filtration and air leaks might be big problems. Make sure the air handler is sealed tight to keep attic debris out of the coil, and the filter is of good quality, (pleated works well) tightly-fitted and changed frequently.
There is often a connection between a clogged evaporator coil and a failed compressor. If the coil is clogged and insufficiant air passes through to warm the refrigerant up and cause it to completely boil, a percentage of the refrigerant may return to the compressor in liquid form, and cause premature failure.
If you have a tightly-sealed air handler with good filtration, the evaporatore coil may never need to be cleaned again. It may be worthwhile to investigate a germicidal lamp to control mold growth on the coil.
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