My Condenser Unit Fan runs slow for about a minute, then stops, then, after a few seconds, the compressor stops. After waiting a few minutes, I can restart but only after resetting the High Pressure Switch. This is a Lennox HS9-311-1P.
I had a problem a few weeks ago when turning on unit for the first time for the season. The unit was not getting power. Cleaned, filed, the Compressor Contactor contacts and all was well. Checked now and refiled again. Getting plenty of power and current. I will replace the contactor.
Is the problem the fan or the fan motor capacitor or should I replace both?? Or what else can it be???
You can never get the contacts filed where both halves will mate perfectly flat. There will always be high and low spots which will lead to arcing and burning. You can even cause the contacts to weld together causing the outdoor unit to run all the time. Which is not good for the compressor because liquid refrigerant will be slugging the pistons when the indoor fan shuts off. Ie. No heat transfer refrigerant will not flash to gas.
Sounds like the condenser fan motor or the run capacitor. When replacing a motor always change the run capacitor.
Observe all electrical safety when working on your unit.
Take a poloroid or digital photo of all wire connections before you proceed in case you forget.
Measure distance from motor housing to fan hub and record distance for install on new motor.
Soak the fan motor shaft with WD40 or PB Blaster to loosen years of rust. If the fan does not come off. Please do not hammer it. Take it down to your local auto repair shop and have them use their arbor press to press the old shaft out.
Gary Reecher, CM HVAC Service Tech
When the problem is fixed please post as to what was the cause. We like feedback information.