Please read first for A/C repair

Old 06-21-22, 02:00 PM
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Exclamation Please read first for A/C repair

It can be hazardous to push the contactor in manually. If the compressor is shorted there could be a large arc. Never use anything to hold the contactor manually engaged.

When working directly around the compressor.... wear safety glasses in the event of a refrigerant breach.

When servicing systems keep in mind that most thermostats have a five minute turn on delay to reduce short cycling when changing set temperature. Many condensers also have a three to five minute time delay board to reduce short cycling in the event of power failure.

Biggest complaint is the outside condenser is not operating. There is a logical way to test the system and arrive at the problem. Disconnect power - pull service pullout. Look at the diagram. The 24vAC enters the condenser in the wiring hatch where the main AC wiring enters. Check for 24v there. If it's there but not at the contactor.... one of the pressure switches is open. This problem occurs mainly when low on a charge. If you have 24v on the contactor and it doesn't close.... the coil is open.

If the compressor is running and the fan is not.... you may have a defective capacitor. Replacing the capacitor is a logical and cost effective first step. Make sure power is disconnected and short across the capacitor to insure it's discharged.

If the fan isn't running or is running slow.... the compressor will shut down on overload.... high heat. It could take upwards to an hour for the compressor to cool off and restart. A compressor should not be allowed to cycle on overload as it will shorten its life.

If you have a heat pump system you will have more than two wires to the condenser.
In that case.... start a thread.

Another common problem is A/C drain pan overflowing.

There are two drain connections. Primary and secondary.
Primary is slightly lower in the unit. (not always easy to see but is usually marked on the unit)
When the primary clogs the water rises and comes out the secondary drain.
If no secondary connection.... the internal pan will overflow.
To clean the drain pan...... turn off the A/C (blower)
Pour one cup of bleach followed by 1/2 gallon of warm/hot water into the secondary pipe.
The bleach and water will come out the primary drain line.
This will clean the pan and the drain line.
Should be done every year.
This is only a typical A/C system. Every system has different drain setups.

If you don't understand this sticky... start your own thread.
Additions will be made to this sticky.

Last edited by PJmax; 07-01-24 at 05:33 PM. Reason: updated
cigarmikl, CircuitBreaker, pb24578 voted this post useful.

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