The reason I ask is that my elderly Mother lives alone in her house in Florida, and too often she has suffered no-cooling due to icing of the A coil.

Most of the trouble for the last 3 years was due to an improper T-sat installation where the service did not change the dip switces for a single stage t-sat. The fans speed stayed on the low setting, and icing was every 5 mos on average.

Now, after the compressor was beat to death, she has a new system as of last year, and once again no cooling due to a 6" thk build-up of ice on the a-coil, that took overnite to defrost, and in total, made for a day and a half of humid 85F in the house!

It seems to me that a simple resistive or K-type temperature sensor could be mounted on the side of the A-coil where the ice starts to build, that turns off the compressor only until the ice melts, to prevent the extreme build up that she has now. She would notice the rise in temps, especially since I got her a hand held radiant gun with "lazer targeting" to read a typical flow temp off the grill (not exact grill temp due to distance).

Any help would be greatly appreciated,

Kevin

PS: I installed an undersized 2.5T Sears unit with precharged lines 25 years ago on my home in Delaware, and never had a leak ...... but never had Florida anual temp & humidity.