I just bought a new thermostat and installed it (RiteTemp 8085C). I have a two stage Carrier heat pump (this unit claims to be compatable with two-stage heat pumps). After wiring the thing up, it seems as though the first stage heat is not working properly. Here is a summary of what I did:

Original -> New
O -> O
W2 -> W2
E -> not connected
G -> G
R -> RH (with jumper to RC)
C -> C
Y -> Y (with jumper to W)

When the first stage heat is used, it appears to actually be running the air conditioner (or possibly just running the coolant pump with no compression/expansion). I touched the duct entering the heat pump and it felt about 10 degrees WARMER than the duct leading out of the pump! I double and triple-checked all of the connections and found nothing wrong. The wiring I have completely matches the diagram that came with the thermostat. Any idea what has gone wrong?

I am at the point where I am considering returning the thermostat and using my old one instead.

Thanks!

Chihuahua

 

Do you have an extra wire there? I looked at the web page, and looks like B maybe your extra wire.. Try that in the O slot...

 

Ulimately there were 2 extra wires. There was a wire which was connected to "E" on the original thermostat and a wire which was originally connected to nothing.

The instructions on the thermostat installation said not to connect E. I do not know what the other wire is. But, it is my understanding that you do not connect both O and B (just one). O drives the changeover valve in cooling and B drives the change over valve in heating (of which you only need one of course). I heard back from the manufacturer of the thermostat and they said I have seemingly connected everything properly.

After leaving the heat pump off for a day, and then turning it back on it SEEMS to be working fine now. I am going to monitor it for a couple days and see if it goes back to misbehaving.

 

One thing you want to think of here with the heat pump .When you put a programmable tstat on them and it goes to set back to save fuel cost. Thats just fine. But when it goes to pick back up the heat most of the time it will turn on the strip heater to help so you blow what you have saved by the set back. Most units have like a cop Of 30. That mean like at 30o out side you get 3 times more heat for a dollar than you will out of the strip heaters for a dollar.

ED

 

I understand that it is best to leave the temperature constant during the heating months, but I read somewhere that it will save money during the cooling months...is this right?

There is also a possibilty that I will get a gas furnace in the near future, and at that time, the thermostat will come in handy during the heating months as well.

Thanks for the response!

 

Go to http://www.warmair.net to compare fuel cost for where you are. You could put the gas furnace under the heat pump. Its not just the temp in the summer in a home its more in what the humidity stays at in the home if you feeel cool or not.

ED