# AC compressor fan comes on for a couple seconds then shuts down.



## tpeerson (May 26, 2010)

Looking for insight please to a possible cause of this problem.

When the contactor engages the compressor fan comes on for 1, maybe 2 seconds and then the contactor disengages, turning off the fan. The fan isn't on long enought to get up to speed. Press on the contactor (with an insullated screwdriver) and the fan will come up to speed. Remove the screwdriver and the contactor disengages. 

Thanks!


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## kok328 (Jun 4, 2010)

check for constant 24VAC to the coil on the contactor.  That's what engages the contactor.  You may have a low pressure switch that is cutting power to the coil.


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## thegoodguy (Jun 26, 2014)

i have a trane package unit. 3 ton compressor. the contactor closes but only for about 10 minutes or so. then makes clicking noises like if it opens and closes really fast. changed compressor,relay,lockout relay, tranformer,contactor,capacitor. ? any idea what it could be ?


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## thegoodguy (Jun 26, 2014)

how many low pressure switching would be in this unit? and how do i test to see if there good?


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## Wuzzat? (Jun 26, 2014)

thegoodguy said:


> for about 10 minutes or so. then makes clicking noises like if it opens and closes really fast.


I'd look for a bad connection to account for this oscillation, just like dirty battery terminals will make your starter relay click rapidly.  
This connection might take 10 minutes to heat up and become flaky and it will probably feel hot in the final minutes.  And, the 240v measured at your unit on an analog meter will have the needle waving back and forth.


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