Tip & How-To about Heating & Cooling
Wiring up a compressor
If there is an identifying mark on one side of the capacitor such as a Dash, Red paint or arrow pointing one direction that will be the run side of the capacitor, if no marks you can use either side for start or run.
If you have three terminals on the capacitor you have a dual capacitor, (C = RUN compressor and fan) (HERM = compressor start) and (FAN is fan start wire).
The Start wire goes to one side of the run capacitor it will be the only wire on that side of the capacitor.
The Run wire goes to the terminal side (T2) of the contactor, it will have another
wire from that terminal to the run capacitor which is the opposite side of the start wire.
The Common wire will go to the other side of the contactor (T1).
Start from the capacitor to terminal #1 on start relay There should be another wire from
here to start on the compressor.
Common from contactor (T1) to terminal #5 on start relay. There should be a wire from this terminal to the Common terminal on the compressor.(there will not be a capacitor in this circuit)
Run from the other side of the contactor (T2) to the start capacitor and from the other
Side of the start capacitor to terminal #2 on the start relay. There should also be a wire from this
Terminal to Run on the compressor.
Posted by Bill Long on
Aug 24, 2011 | Heating & Cooling
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