Disconnect On Outside Unit Pull But Contactor Still Engaged - HVAC - DIY Chatroom Home Improvement Forum

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Old 07-21-2012, 06:09 PM   #1
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disconnect on outside unit pull but contactor still engaged

I was trying to troubleshoot my ac unit and the first thing I did was to disconnect it from its power source when I did the contactor was still engaged ,went inside and turned the unit of at the thermostat ,went back out side and contactor was disengaged , checked voltage at L1 and L2 had proper voltage, turned thermostat to cool contactor did not engage ,pushed in contactor and nothing what gives?


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Old 07-21-2012, 06:23 PM   #2
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the control voltage comes from the furnace transformer by way of the stat setting...might be a time delay if you ran outside.pushing in the contactor and the compressor or condenser fan didn't run ?is the disconnect a knfe disconnect or fused when you shut it off with the fuses in the pull plate...where are you reading L1-L2


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Old 07-21-2012, 07:32 PM   #3
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When trouble shooting it is usually best to one thing at a time. By your post you may be just trying to go to fast and bouncing all around. The disconnect only turns the outside power off. The contactors is pulled in by control voltage. This voltage comes from the inside unit which is not effected by the outside disconnect.

What are the symptoms which cause you to initially trouble shoot the unit?
Was the disconnect back in when you got your voltage reading? It should have been to get the reading

If you have 240 volts at the contactor but the unit does not run (no fan, no compressor) a likely cause could be a capacitor. The thermostat may not have pulled in by itself due to a time delay at the unit or thermostat after you turned it off.
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