I have 2 units (model ptc123b50ambp) where the control boards have burnt (melted the center relay (I don't have the board handy so I can't tell ya what the relay is for)) what could cause this problem?
One unit, where only the wire was burnt (at the capacitor) was bought over a year ago, but only put into service a few months ago, the other, I don't really know how old, but the relay for the a/c compressor power seems to be where the problem started(?)
One unit, where only the wire was burnt (at the capacitor) was bought over a year ago, but only put into service a few months ago, the other, I don't really know how old, but the relay for the a/c compressor power seems to be where the problem started(?)
Make sure everything is wired up properly. make sure that your 24 volts is correct(low voltage and your 120 volt transformer.) make sure the breaker is the right rating /amp. check nameplate so you will know proper information
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
Sounds like a bad relay. Unfortunately that relay is on a circuit board. You can bypass the board, I will help you if it's actually the case. But, to test it, turn power off to unit, on the circuit board you will have a relay(In the indoor unit) on this relay you have three wires, swap the two wires that are right next to each other. You will see 2 wires very close to one another and another off to the side. Swap the 2 that ARE RIGHT NEXT TO EACH OTHER. Turn power back on to unit. This should make the fan run non stop all the time. If it does let me know.
Sounds like either a stuck relay or stuck contactor. Not a difficult fix if you have right part. Turn power off and locate how high voltage gets to the heat strip. If there is a black box on a circuit board than it would be that whole piece.
If it has humidity control and the cool is still on but set temp is higher than the room temp, the humidity control will override set temp. If it has no %rh control then it probably has a circuit board fault; micro relay is stuck closed and board needs to be replaced. Its probably the circuit board. On it, there is a little black box(s). About 1" X 1/2" in size. With long run times the small contacts inside will fuse/melt together.
Almost certainly it is a bad relay on the circuit board. Sometimes you can slap the side of the unit by the control box to temporarily unstick the relay, after which the heat will come on for a cycle or two. There are two relays on the circuit board marked "heater 1" and "heater 2". You can order a new circuit board for about $100 or replace the relays at $4 apiece (order online from Digi-Key, requires solder connections). Part number JTN1a-PA-F-DC5V.
THEY ARE SOLDERED ON AND SNAPPED ON THROUGH A CONNECTOR ALREADY MOUNTED ON THE BOARD AND THEN SOME OF THESE CONNECTORS HAVE WIRES LEADING TO AN EXTERNAL RELAY. NOT ALL RELAYS ARE ON THE BOARD.. THE BOARD ALSO CONTAINS RESISTORS AND SWITCHES CALLED LIMIT SWITCHES AND ROLL OUT SWITCHES. MOST ARE SOLDERED BUT ALL RELAYS ARE NOT LIMITED TO JUST THE BOARD.
The reversing valve may be stuck or it has a burnt solenoid coil. Also, check the defrost relay accross the contacts with an ohmmeter and see if it's bad. Goodman heat pumps also trip on high pressure. There's a resettable switch on some units with a red button. However, I think the problem is in the defrost circuit or reversing valve. If your electric heat is on, change the board.
In more rare scenarios the 24v activated fan relay that is soldered to the circuit board can cause this same problem. I agree with Therinnaiguy, If the fuse is blown 90+% of the time there is a short in the 24 volt control system.
One unit, where only the wire was burnt (at the capacitor) was bought over a year ago, but only put into service a few months ago, the other, I don't really know how old, but the relay for the a/c compressor power seems to be where the problem started(?)
A combination of things could cause that but I would lean towards a loose connection . How old is unit?
×