QuestionI looked at the upper control board, I didn't see any scorched or burned spots any where on the board. I know that may or may not be the case with a relay. Would you happen to know which relay may be causing the problem, and if there is an easy way to check the relay. Thanks again for your prompt reply and help. James
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It is a wall thermostat. It is not a digital type, it has green lights. It has a horizontal temperature control slide. On the circuit board of Thermostat it says Model # 5054. If you need additional information please let me know. Thank you for your response.
James
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I have performed the capacitor test and Compressor tests as you recommended. Readings are normal as per your instructions. What do you recommend next. Thanks James
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DouTherm Model # 58915 603, S/n not available, DuoTherm Tstat Model # 5054, S/N not available.
My A/c was cooling my RV to 74* in 95* weather. It suddenly quit cooling. The Fan was running, but the compressor would not and hasn't kicked in since. I checked the overload relay, it has continuity. I checked the Compressor each of the C S R poles were 0 ohms, check the CSR poles to compressor housing showed infinite ohms. I have checked the Start capacitor with ohm meter. The Run capacitor was also checked with ohm meter. The capacitors all show the ohm reading which then falls back to infinity, none of the posts are shorted to each other, neither are shorted to their case. With the unit running for five minutes to give compressor time to turn on, I checked the voltage on each of the Run capacitor posts, there was 116.7 VAC on each post. There was 116.7 VAC on both sides of the compressor start relay. There was 116.7 VAC on each of the C, S, R, post of the compressor. The Compressor does not heat up as if it's trying to start and the overload switch doesn't open. I hope you have some idea where I may look to see if this unit can be prepared. Thank you for your help.
Answer -
Capacitors should be checked with an Analog meter. Discharge the capacitor. You should not see any continuity from the case to either post. Between the posts, set the meter to the highest setting and the needle should move toward zero then slowly back toward infinity. Reverse the leads and repeat the test. If little movement is noticed go to the next lower scale.
Remove the wires from the compressor, there should be continuity between all 3 posts. If there isn't, the windings are open and the compressor is not any good.
Of course always disconnect power before any work begins!
Garry
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A question I failed to ask, are the controls on the ceiling assembly or do you have a wall thermostat?
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short of having a bad compressor, you may be experiencing a bad control system. The replacement parts for that system is not available and you have to upgrade to the comfort control system. I know you have seen voltage at the proper connections, however those may not be the same when under a load, and that would be caused by a bad relay in the upper control board.
Garry
Answerthe relays are soldered on the board, pretty dificult to test that way. this is common action for this board however. There usually is not any burnt marks or anything when these fail, the relay contacts usually fail and do not make contact any longer.
