Author Topic: Rheem Heat Pump Outdoor Temperature Sensor issue  (Read 4565 times)

Offline strut

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Rheem Heat Pump Outdoor Temperature Sensor issue
« on: October 24, 2008, 03:48:51 PM »
Hi, I have a Rheem Heat Pump (Classic Series) with a remote temperature sensor installed. I also have a RobertShaw thermostat. The unit is about 4 years old. The remote outdoor temperature sensor has been giving me some wrong readings lately on my thermostat. For instance, it sometimes reads -40 degrees centrigrade and sometimes the outdoor temperature display will not appear at all. I opened the pump door last weekend and after making sure all the connections were OK (and therefore moving some wires around), I noticed my readings got much better but this morning my readings were once again 30 degrees below the outdoor temperature. My questions are:

- There is a black wire leading out of the control unit that terminates nowhere. The end of the wire is surrounded by black rubber or plastic. Is this the temperature sensor? It looks so to me but I wanted to be sure before going further.
- I also noticed this black wire is soldered on the control unit board. Is is replaceable then? I suppose I could solder a new one on the board but I am not even sure if I can buy a replacement without replacing the whole control unit.

Should I be looking more into another wire, leading from the board to the house?

I made sure all the junctions, etc.. between the pump's wires and those going in the house were bound nicely.

Anyone have a similar problem? If so, I would appreciate some feedback on what it could be.

Offline TECH X

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Re: Rheem Heat Pump Outdoor Temperature Sensor issue
« Reply #1 on: October 25, 2008, 10:34:34 AM »
The black rubber plastic end you describe sounds like the sensor.  It sounds like the sensor if faulty.  Usually the sensor is easy to disconnect and replace.  I'm not exactly sure of the type you have.  It would be a very poor design if an entire control board had to be changed because of a faulty sensor.