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AC blower shutting on and off every 2-3 min after new fan motor and capacitors!

AC blower shutting on and off every 2-3 min after new fan motor and capacitors!

Old 07-27-11, 08:58 PM
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AC blower shutting on and off every 2-3 min after new fan motor and capacitors!

My first post! (Although I already typed it out once and got booted before I could post it!) Once again.

Helping out a friend who has inherited a money pit and he can't swing the $6,413 quote he received to replace his AC unit inside and out. (The repairman didn't even want to diagnose, just wanted to replace). AC quit running a week ago and the blower has run continuously to move air within the house. South Carolina has been a scorcher too! He asked me to take a look and I found the outside fan motor to be stopped and humming loudly. The motor would restart with the push of a screwdriver so I assumed the installed dual capacitor had crapped out and figured for a few extra bucks I'd go ahead and replace the fan motor as well.

Hoofed it off to the local HVAC supply store and found they carried neither the capacitor nor the motor I needed so they suggested a substitute. I swapped the old Emerson 1/5hp fan motor for a new 1/6hp motor. Each had the same 1075rpm, 208-230v, etc. Instead of the dual capacitor (which also had an installed booster) I swapped it for an OVAL 5mfd 440v for the motor and a ROUND 40mfd 440v for the compressor. Wired it up and was back in business, so I thought.

Everything seemed good. Compressor lines were cold and very warm for each, motor was blowing up and out of the unit. Even the inside was cooling off.

For maybe 2-3 minutes then the inside blower shuts off. Sits for 2-3 minutes then it kicks back on again with nice cold air which slowly warms slightly then the blower kicks off again (2-3min). Again, up to this point the blower had been running continuously until the changes to the outside unit were made so I wouldn't have thought the blower would suddenly go bad.

Tomorrow I plan on checking the filter and A-coils and reseting any switches on the main HVAC unit as all the outside breaker flipping may thrown something off. Maybe a thermostat is in the works too.

Any thoughts or suggestions? Thanks in advance.
Old 07-28-11, 02:56 PM
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Join Date: Jan 2011
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well, 1st thing is that you cant lower the Horse Power like you did, you can go up, but not down.

As for the blower issue. check signal from thermostat between G and C while the unit is acting up.... beyond that it could be the relay or controller for the blower.

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