I don't know how many here have a whole house genset, but this could also apply to times when the power in your area "blips" or "browns out" sporadically.
OK, here goes.
My genset ran it's normal "loaded" exercise cycle (same as it has for the last year).
When it transfers from "utility" to "genset", my central A/C senses the very brief loss of power and shuts down.
The A/C starts it's 5 min. timer for restarting (which is built into all central A/C units, I'm told).
It follows the same routine when the retransfer from "genset" to "utility" takes place.
But this time, the A/C did not restart after the retransfer to "utility".
So after waiting 10 minutes (for the 5 min. timer) I flipped the A/C breaker off and then back on (since the fancy high efficiency A/C has a logic board, I figured maybe it needed a reboot)
Still no go after 10 more minutes.
Tried that routine once more, with the same negative results.
Every time, the indoor and outdoor fans would run, but the compressor didn't.
Since a single contactor turns on both of the fans and the compressor, so something was screwy.
If the fans ran, then so should the compressor (after the 5 min. delay)
So since it was 95F today and will be 96F tomorrow, I called my A/C guy (who happens to be my nephew).
By this time it's already 7:30pm.
He advised me that he sees this all the time with Generac units.
When they transfer, they somehow confuse the A/C and it thinks it has been "short-cycled" and it locks the compressor out.
I reminded him that I have a Kohler, not a crap Generac and have had it exercising once every month for the last year and never had a single problem.
(His response was "OK, so?")
He told me to turn off the breaker, and leave it off for about 2 hrs.
That gives the logic board time to completely discharge any power in it capacitors (we're not talking about the run/start cap, but the caps that filter power on the logic board), and that should release the "short cycle lockout".
Sure enough, when I turned the breaker back on after 2 hrs., the A/C started right up.
He said he uses the 2hr. time frame because it always works (when a "short-cycle lockout" is the problem), and while it may actually take less time, knowing exactly how much less, better safe that sorry.
When the A/C doesn't work people get irritated and if you stand around for an hour and it doesn't work when you turn the breaker back on, only to have you tell them you have to stand around for another 2 hours, well you can imagine the results.
BTW, his service calls are a flat rate, not by the hour, so that's not a factor in the time frame.
A/C's always seem to screw up in the evening or on a weekend, don't they?
Hopefully if this happens to you, this might save you an expensive service call, if you try this first.
OK, here goes.
My genset ran it's normal "loaded" exercise cycle (same as it has for the last year).
When it transfers from "utility" to "genset", my central A/C senses the very brief loss of power and shuts down.
The A/C starts it's 5 min. timer for restarting (which is built into all central A/C units, I'm told).
It follows the same routine when the retransfer from "genset" to "utility" takes place.
But this time, the A/C did not restart after the retransfer to "utility".
So after waiting 10 minutes (for the 5 min. timer) I flipped the A/C breaker off and then back on (since the fancy high efficiency A/C has a logic board, I figured maybe it needed a reboot)
Still no go after 10 more minutes.
Tried that routine once more, with the same negative results.
Every time, the indoor and outdoor fans would run, but the compressor didn't.
Since a single contactor turns on both of the fans and the compressor, so something was screwy.
If the fans ran, then so should the compressor (after the 5 min. delay)
So since it was 95F today and will be 96F tomorrow, I called my A/C guy (who happens to be my nephew).
By this time it's already 7:30pm.
He advised me that he sees this all the time with Generac units.
When they transfer, they somehow confuse the A/C and it thinks it has been "short-cycled" and it locks the compressor out.
I reminded him that I have a Kohler, not a crap Generac and have had it exercising once every month for the last year and never had a single problem.
(His response was "OK, so?")
He told me to turn off the breaker, and leave it off for about 2 hrs.
That gives the logic board time to completely discharge any power in it capacitors (we're not talking about the run/start cap, but the caps that filter power on the logic board), and that should release the "short cycle lockout".
Sure enough, when I turned the breaker back on after 2 hrs., the A/C started right up.
He said he uses the 2hr. time frame because it always works (when a "short-cycle lockout" is the problem), and while it may actually take less time, knowing exactly how much less, better safe that sorry.
When the A/C doesn't work people get irritated and if you stand around for an hour and it doesn't work when you turn the breaker back on, only to have you tell them you have to stand around for another 2 hours, well you can imagine the results.
BTW, his service calls are a flat rate, not by the hour, so that's not a factor in the time frame.
A/C's always seem to screw up in the evening or on a weekend, don't they?
Hopefully if this happens to you, this might save you an expensive service call, if you try this first.