Replaced contactor but AC still not running
#1
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Replaced contactor but AC still not running
Brand New contactor input I'm getting 220 V but getting nothing on the output side or coils. Goodman package unit. Capacitor looks good.
Thoughts ?
Thanks.
Thoughts ?
Thanks.
#2
If you aren't getting low voltage to the contactor coils, you won't have 240V (not 220) on the output. You need to measure for AC voltage (28VAC?) on the wires coming from the inside unit when the stat is calling for cool. The outside unit often has safety switches for high and low pressure that will prevent starting. They often have times that will require you to wait 5 or 10 min after reapplying power before it will start.
Might help to know brand and models of your system.
Might help to know brand and models of your system.
#4
You'll need to locate the thermostat wiring where it enters and connects to the unit. In cooling mode you'll need to measure 24vac from C to Y, from C to O and from C to G. It's the C to Y that we are really interested in. If that is present you will need to use the schematic off the service door to locate the high and low pressure switches.... if used. The service manual shows them as optional.
#6
It might not be the stat...in fact it's unlikely. What can happen is that a fuse blows on a transformer that supplies the 24V. Happens kind of often if all power isn't shut off and wires get shorted out.
It may be a broken or pinched wire. You need to check for the 24V. Since it's a package unit, it should be easy to find.
It may be a broken or pinched wire. You need to check for the 24V. Since it's a package unit, it should be easy to find.
#9
Now you'll have to go back to post 4 and make those tests.
Thermostats can go bad.... that's why you use a meter to make tests.
Thermostats can go bad.... that's why you use a meter to make tests.