Fuses Blowing on Circuit Board

portac1058 · #1 Jul 22, 2008, 05:36 PM

The 3A fuse on my circuit board keeps on blowing. After I replace the fuse, the evaporator coil blower will run just fine, but, when I try to turn on the A/C, the fuse blows, everything shuts down and then nothing comes on. I'm guessing the relay inside the condensing unit is probably shorting out. Does this sound reasonable? Can I test the relay to see if it is faulty?

Stratmando · Jul 22, 2008, 05:46 PM

Look at the windings on Contactor for discoloration or burnt. For a quick test remove both wires from contactor coil, insulate, turn to cool. if it still blows, short may be in control wiring, also, try Fan only, to make sure not blower relay/contactor not shorted.

portac1058 · Jul 25, 2008, 12:29 PM

Pulled the 24v wires off the outside unit and it didn't trip when on "cool". I replaced the contactor even though it didn't look burnt and unit is only 18 months old. Condenser fired right up without blowing the fuse! Works fine now. Thanks.

Stratmando · Jul 25, 2008, 03:16 PM

Good Deal.



At Ask Me Help Desk you can ask questions in any topic and have them answered for free by our experts. To ask questions or participate in answering them you must register for a free account. By registering you will be able to: Get free answers from experts in any of our 300+ topics. Accept money for answers that you provide. Communicate privately with other members (PM). See fewer ads. Sign Up!