GA7FF overheats, element outlet over temp. Fans are not coming on.

by Forrest Mayhugh
(Mansfield, Texas, USA)

I have two ga77ff with what appears to be identical issues both had been serviced recently and both are over heating. The element outlet temp is high. One compressor started this fault a month ago and had two compressor repairmen look into it and they could not figure it out. A month later I am now having the same problem with the other compressor. I started to troubleshoot it myself lastnite and found that both compressors air element and oil cooler fans do not kick on when they should. I measured the voltage to the fans when they are triggered to come on at the set temperature and the voltage is only 12 volts on one fan and 10 volts on the other when their individual relay closes to allow the voltage supply to the fans. I would imagine that the voltage would be 230 volts being that the fans are 230 volt fans. I then check the capacitor on each compressor located in the drier section of the compressor thinking it could be that it is not getting start or run voltage due to bad capacitor, but both check out so I am in need of some understanding how the control circuit works but why it is not recieving the adequate voltage to power the fans. I have diagrams but too small to read. Couldn't find them online so maybe if I could at least have someone share a diagram download it could help me. Thanks

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Oct 09, 2016
GA7FF overheats, Fans are not coming on
by: Doug in

Sure sounds like some part defect.

Did you check that the relays have the expected 230V "across" the contacts and/or the fans? They may show less or no voltage to ground, depending on your commercial power.

Speaking of which, have you checked the power coming into the machines? Perhaps that's flaky and causing the common problem.

Let us know what you find out, please.

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