ghostrider20

Hi all, sorry for posting this here, but I just had to tap into the wealth of knowledge here for some help. I am visiting family in Scottsdale and the thermostat on the lower level is INOP. I went to Home Depot and not knowing which kind I needed I bought a couple of differant kinds.

I am not even sure what kind of system this is. The covers are all on the inside unit so no name is visible. I am tool limited and really do not want to tear it apart.

It is all electric, i;e no incoming gas. There are dual outside condensors, and a thermostat upstairs and downstairs. The downstairs thermostat is the one needing to be replaced.

The old Thermostat had the following wires and this is where they were hooked up to on the old thermostat.

WHITE WIRE - went to the "O" srew connection
GREEN WIRE - Went to the "G" screw connection
RED WIRE - Went to the RC/RH screw, and they were jumpere
YELLOW - went to the "Y" and the "W" screw connections

The New thermostat has a place for all the wires/letters, but the only thing that I can get to work is the fan. ?? An electrician was here on Saturday (Late) and diagnosed the problem, but did not have a new thermostat with him.

The new thermostat is Ritetemp 8050C

Any thoughts?

Thanks
Mark

stingrayl76

Can't answer your question, but this link may be of some help.
http://www.ritetemp-thermostats.com/8050C.html

rahzip

Here is a color break down

Red is 24v hot
White is for heat
Green is for the fan
Yellow is for the A/C

Upon a call for cooling the R should send power to the Y & G terminals.

Try connecting the Red to RC only. See if that helps.
I am not sure why they would have the Yellow going to the Y & W

Let me know if this helps.

ghostrider20

Thanks-

I tied all the wires together, and the AC is blowing cold

The unit is a goodman airhandler. There are two of them, one upstairs, one downstairs.

Is an airhandler the same thing as a heat pump?

Thanks
Mark

Mr D.

The Air Handler does just what the name implies, handles air via a fan motor, fan cage and evaporator. The heat pump part is outside and consists of a pump and condenser.

Think of it in Vette terms: The a/c pump and condenser that are mounted in front of the motor stay outside. The evaporator and fan on the firewall are inside.

Cmacsvette

Mark

It sounds to me like you have heat pumps.
As said before:
Terminal R is 24 volts normally a red wire
Terminal W is heat normally a white wire
Terminal O is the reversing valve normally a orange wire
Terminal G is the fan relay normally a green wire
Terminal Y is the compressor contactor normally a yellow wire
Terminal C is com could be any color, in fact, any of the above wire colors could be a mix. The standards in the industry though normally follow the above.
The O terminal is only for heat pumps and only heat pumps have a reversing valve. This valve is used to change the direction of the gas, either for heat or cool. If you have a heat pump, you (normally) have elec. strip heat in the air handler to back up the heat pump (outdoor unit). The W terminal is normally your 2nd stage heat (the elec. heat) and is used to supplment the heat pump in a call for heat when needed. If the pump is in defrost and a call for heat is needed, then the elec heat will be called upon to satisfy the stat also. Not all heat pumps will have back up heat in their air handler, many factors depend, like what part of the country you live etc. It also depends on how many BTU'S are generated in the space year around etc.
In most single stage H/P, on a call for heat, 24 volts is sent to the Y and G terminals. In this same H/P, on a call for cooling, 24 volts is sent to the Y, O and G terminals. There are some H/P that will energize the reversing valve (O) in the call for heat and not energize the O terminal in the cooling mode too.
In your case it sounds like your white wire goes to the reversing valve and is energized for cooling as stated above.
To make sure what is going where, I would suggest looking at the schematic for the outdoor unit and the indoor unit(air handler).
I personally only use Honeywell stats. The new touch screens are the best thing going. You can buy them for A/C or for Heat Pumps. They normally come for 1 heat and 1 cool or up to 3 heat and 2 cool.
Then you go to the installers setup to adjust them for what type system. "Neat O Jet"
Craig

BTW if you don't have aux heat (elec back up) then the Honeywell 1 heat and 1 cool will work for you. Just be sure and do the installer setup for your system.