My Trane A/C Condenser
fan won't run. The unit is model TTP060E100A0 and is about 10 years old. Last night the A/C stopped working. I found that the blower and compressor would run, but the condenser fan would not.
I took the top off the condenser and made the following observations:
Fan blades turn freely by hand
No sign of anything blocking them
Resistance on fan motor leads:
brown - purple 41 ohms
brown - black 40 ohms
purple - black 19 ohms
It looks like the compressor and fan share the same contactor, so that seems to rule out a contactor problem.
Resistance across starter capacitor (series with brown motor lead) - open circuit (even on 20MegOhm setting), and even if I repeatedly reverse the polarity of the tester leads.
Removed capacitor and appears that the capacitor plastic case has heated and blistered near the bottom.
My conclusion is the capacitor is probably bad. My questions:
Does this diagnosis sound correct?
How can I be sure that is the only problem, and that the fan motor is OK and there is not some other problem?