Question:
Our air conditioner's compressor seems to be running long after the fan
turns off. Tonight it ran for over 1 hour after the fan turned off.
Is this a sign of the compressor about to break or is there something I can
do to troubleshoot this problem? The air filter is clean and the unit is
dust and dirt free. It's mounted on our roof and we live in Arizona. What
is the typical life expectancy of an air compressor?
Answer:
If you are talking about the inside fan (the one in the furnace / air
handler) then most likely you have a sticking contactor. Allowing the
compressor / condenser to continue running with no load on it from the
evaporator (fan) isn't good for it, and will definitely shorten its
life. The contactor is inside the condensing unit and generally isn't
something that a homeowner should try to fix (high voltages and all
that). Time to call a professional.
I've seen published numbers for A/C life from eight to 15 years. I've
personally had well maintained systems go twenty years or more, but a
system of that vintage today is inefficient compared to what is
available now. At some point you are better off installing a new system
than continuing to have the old one repaired.
