How to Test an Air Conditioner Compressor on a Heat Pump
You've had your thermostat dialed all the way down for hours, but the heat pump doesn't seem to be keeping up with the scorching summer day. You've checked all the windows and doors, but no matter how much you seal the heat outside, it's not getting any cooler inside, and you begin to dread an air conditioner repair in the middle of the summer. Education, however, is often the key, and with a little bit of study and a few tools, you can at least diagnose the problem and maybe fix it on your own. Does this Spark an idea?
Other People Are Reading
Instructions
-
-
1
Go over the problem in your head. If you suspect the compressor, you are likely getting air flow, but the air is not cooled sufficiently. For other problems, such as a complete failure to turn on, switches, wiring, thermostats and other components may be involved. Heat pumps are complicated units made up of many parts and systems. A step-by-step approach is required.
-
2
Eliminate the obvious problems first. Check the filters. Clogged filters are the biggest cause of heat pump underperformance in units that are otherwise working well, or units that are well within their usable life span.
-
-
3
Clean the filter if it is clogged, and move on to the blower. If it is also dirty, remove the fan and clean it with a foaming type cleaner and water. Clean the housing before you replace the fan.
-
4
Check the condenser coil. If you had dirty filters and a clogged fan, you likely will see a big block of ice on the condenser. You'll need to wait until the ice is completely melted before turning the unit on again. You can speed the process by pouring warm water over it. Ensure that the drainage gutter is not clogged.
-
5
Find the reset button on the compressor. It is usually red and will be stuck in the out position if it has been tripped. Try pressing it back in. If it won't stay depressed, wait until the motor cools and try again.
-
6
Test the impedance of the compressor terminals. Remove the electrical cover, detach the wires and attach the ohmmeter between the terminals. Test each terminal (there should be three). You should read low impedance from terminal to terminal, about a hundred ohm. If you get high impedance numbers, your compressor likely has a broken wire and it's time for a replacement. Bad bearings or shorts also can cause a compressor to fail, but testing for those problems is at the professional level, and a diagnosis of either of them results in a need for a new compressor.
-
1
Tips & Warnings
Have your system recharged according to the owner's manual.
Follow the maintenance guidelines in your owner's manual and have your unit serviced every two years.
Never put a new compressor in an otherwise aging unit. Upgrade.
