Outside fan runs constantly Aux Heat only 50%

fan motor over heating replace

Unless you just installed or had the thermostat installed recently, I would not point at the thermostat as the problem. With what you have described I would suggest have your units serviced as it sounds like a loss of charge, or failed defrost control board. The "Aux" comes on when the unit is using secondary heating (electric heat strips). That occurs when the demand temperature (what you set it to) in Heat mode is more than the current room temperature, usually ~2-4 degrees higher. Also happens in defrost mode. Defrost is a heat pump cycle that melts any build up of ice on the condenser unit (outside unit). That process is simply the unit running in cool mode which will heat up the outside unit to melt any ice. Defrost cycles vary with manufacture but usually you can tell if is in defrost by looking at the outside unit, during defrost the unit will be warm or hot sometimes there is steam and the compressor will be running but not the fan. Defrost only happens on heat pumps in "Heat" mode. Rheem has a 10 yr compressor and parts warranty, so call the installer or Rheem authorized service company.

Mike I would contact Rheem directly or just take it out and go to a store and match it up
You could do a search but think the other two ways will be a lot faster

What's wrong with your current AHU? Any Ruud dealer can assist you. Most 4 ton units work with r-22 or 410a. As a side note, most parts in an air handler can be replaced unless the case is rusted thru.

Mine doesn't have a plastic bag and the diagram on the cover is too faded to read is there somewhere online I could get a wiring diagram for the Rheem RPKA-049JAZ heat pump?

TURN THE POWER OFF TO THE UNIT. TAKE THE BACK PANEL OF OF THE HEAT PUMP AND LOOK FOR A SQUARE PLASTIC BAG FASTENED TO THE INSIDE OF THE UNIT, IT MAY BE LOCATED BY THE CONTACTS AND SYSTEM WIRING OR ON THE PANEL ITSELF. REMOVE THE PAPER FROM THE PLASTIC AND THIS SHOULD CONTAIN YOUR WIRING DIAGRAM. ALSO LOOK ON THE BACK OF THE PANEL ITSELF FOR THE DIAGRAM. SOMETIMES THE DIGRAM IS PRINTED THERE.

no this is not normal. the fan should stop running when the thermostat is satisfied or when the heat pump goes into defrost mode. if it is running nonstop, there is a contactor that operates the fan and compressor that if it sticks will get line voltage to it. you would have to take the cover off of the outside unit and turn the thermostat to off. If the fan continues to run, you need a new contactor.

I believe the unit you are describing is a heat pump. Heat pump are great when the temperature isn't below 30 With low ambient temps. outside it is much more efficient and comfortable to run aux. electric heat from the heat pump.

there is a huge problem in the reversing valve. if it works in cooling, there should be no restrictions that would cause that kind of head pressure. the reversing valve is the only thing that could cause this restriction since a/c side works. It is not repairable.

At the low voltage terminal where thermostat wires atttach, and go to stat and ac unit,

there is R red, W white, Y yellow, G green, C common



red is hot white is heat, yellow is cool , green is fan

jumper red to white for heat