Israel
BANNED
Besides all other electrical components of relays, safety and overpressure switches does the outdoor contactor (on condenser unit of heat pump split system) in any way control air handler fan?
Issue is recent...air handler fan began cutting off, then back on cycling over a minute or two both ways while both in heat and cool mode. Pulled thermostat off wall plate to make sure wires looked good, and after replacing found fan wouldn't even come back on...not even intermittently. Checked wires again, did some re-tightening of little lugs and again, fan would come on but then cut off as original symptom. Convinced it was thermostat issue went and replaced it with new one.
Set fan to "on" and it ran as it should for several minutes, no cutting in and out. But when fan setting placed back to auto and called for heat, condenser came on as it should, fan came on and ran...but then started again cycling on and off.
I have had issues and replaced contactors over the years when faulty on condenser, but usually that has been solely due to condenser fan/compressor not operating correctly. (Ants and burned contacts the usual issue).
I believe this contactor was replaced only a few months ago but if there's any possibility of early failure causing this I am not reluctant to throw in another.
I simply (as is obvious) am not an HVAC guy and understand that in certain modes it is possible the air handler fan is in some way (when not set to "ON") dependent upon either a circuit from the condenser unit contactor, or something else I am also ignorant of. Any response is appreciated.
Additional note: Just noticed that when left in "Fan On" setting, fan runs without interruption but at a much slower speed (as evidenced by subdued "noise") but when running in heat mode it sounds far louder (as it usually did when running normally) and also when it cuts in and out. Blades spin freely, and I haven't noticed excess heat (or much at all) in fan housing.
OOps...fan just cut off while in "Fan On" mode with heat and cool "OFF".
And there's one of these inside the air handler...variable speed fan...and kaput circuit board?
Issue is recent...air handler fan began cutting off, then back on cycling over a minute or two both ways while both in heat and cool mode. Pulled thermostat off wall plate to make sure wires looked good, and after replacing found fan wouldn't even come back on...not even intermittently. Checked wires again, did some re-tightening of little lugs and again, fan would come on but then cut off as original symptom. Convinced it was thermostat issue went and replaced it with new one.
Set fan to "on" and it ran as it should for several minutes, no cutting in and out. But when fan setting placed back to auto and called for heat, condenser came on as it should, fan came on and ran...but then started again cycling on and off.
I have had issues and replaced contactors over the years when faulty on condenser, but usually that has been solely due to condenser fan/compressor not operating correctly. (Ants and burned contacts the usual issue).
I believe this contactor was replaced only a few months ago but if there's any possibility of early failure causing this I am not reluctant to throw in another.
I simply (as is obvious) am not an HVAC guy and understand that in certain modes it is possible the air handler fan is in some way (when not set to "ON") dependent upon either a circuit from the condenser unit contactor, or something else I am also ignorant of. Any response is appreciated.
Additional note: Just noticed that when left in "Fan On" setting, fan runs without interruption but at a much slower speed (as evidenced by subdued "noise") but when running in heat mode it sounds far louder (as it usually did when running normally) and also when it cuts in and out. Blades spin freely, and I haven't noticed excess heat (or much at all) in fan housing.
OOps...fan just cut off while in "Fan On" mode with heat and cool "OFF".
And there's one of these inside the air handler...variable speed fan...and kaput circuit board?
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