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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I have two units one and another unit stairs. the heaters

Customer Question

I have two units one for upstairs and another unit for down stairs. the heaters are located in the attic and the air cond units are out side. both stopped working, I'm not sure if they went out together. so far I have only done any checking to the upstair system. I have replaced the start/run capacitor and also the switch relay from the thermostat neither have solved the problem. the heater fan comes on on both system when you turn the thermostat to cool but the out side compressor nor the fan kick on I'm getting 120 volts on each leg coming into the unit and the thermostat appears to be working. ok so whats next. I have the fan motor ready to disconnect figuring that might be my next step. it just seems funny that both units would go out with the same symptoms at the same time.. Am I missing something? Thanks any insight would be greatly appreciated
Submitted: 8 months ago.
Category: HVAC
Expert:  Phil replied 8 months ago.

Hello, check power **between** the two legs that power the outside unit... power from each leg to ground can be feedback when one leg is actually not powered. We can go from there.

Customer: replied 8 months ago.

When I put my meter on one leg at a time I'm showing 120 volts on each leg. I'm not sure I understand what you mean by between

Expert:  Phil replied 8 months ago.

You are checking the voltage incorrectly... do not check one leg at a time.

put one probe of your meter on Line 1 leg, and the other probe of your meter on Line 2 leg.... if you get a zero read one of the legs is not working EVEN THOUGH IT MIGHT READ 120V TO GROUND.

Tell me a lot about your meter, the type you need will have 2 (two) test probes not just one

Customer: replied 8 months ago.

When I put the tester on both the red wires coming into the unit I don' t get any thing tester stays at 000

Expert:  Phil replied 8 months ago.

Thanks, ***** ***** leg of your 230volts is dead, either a blow fuse in the disconnect switch or a faulty breaker... however the two hot wires going into the unit should be different colors....can you send me a photo, use the paper clip icon on the right end of your tool bar for that

Customer: replied 8 months ago.

Sorry to ask this Phil can you send me a phone # ***** a different email everytime. I push te paperclip instead of it taking me to files the screen just goes blank. One problem at a time.

Expert:  Phil replied 8 months ago.

Try loading the picture onto your computer then attaching the file from there, or try the 'attach files' link to the left of your send button

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