thermostat wire diagram / color codes

[Soundguy]

I just got stuck with somebody else's problem.

We use mobile office trailers at our construction sites ( Ge brand if it makes a difference.. ).. anyway.. they have one of those verticale mounted ac's onthe outside back wall.. " The wall mount".. apparrently the one in one of our units we need to use died, and we have another ac apparrently salvaged from a MH. bracketing, ducting, and 3-wire electrical is no problem to hookup.. however the genuises didn't remove the old thermostat from the salvage unit so i could see how it was wired.

'new' ac has 6 wires.. grn, brn, yel, red, blu, wht and is a grandaire.

old unit only has an ATEX sticker on the side electrical access panel. Looking inside near the pump and lines I can see a copelan tag. Old thermostat is a white-rodgers.

Just checking to see if this old thermostat ( since it's hardwired in place ) will be compatible or?

any advice appreciated.

thanks

soundguy

 

[Soundguy]

forgot to add.

wiring in office trailer for thermostat is 5 wire cable, with 4 used..

grn, yel, red, wht are used, and blu is tied off and not used at the thermostat.

soundguy

 

[boxed_R_squared]

forgot to add.

wiring in office trailer for thermostat is 5 wire cable, with 4 used..

grn, yel, red, wht are used, and blu is tied off and not used at the thermostat.

soundguy

Can you provide the name plate data from the unit you are going to install?
also there should be a wiring diagram glued somewhere inside the electrical box that will indicate the terminals which will need to be connected.

The model number for the thermostat would also be helpful as there are severial types which have digital functions. is it a mercury switch type or digital unit?

You may try to look up the correct wiring diagram on the manufactur's web site as well.

if you want to PM me I will try to help you with further information.

Good luck!

 

[boxed_R_squared]

here is the "standard" color code:
Terminal Designation Wire Color Function Description
Rh Red 24 Volt Hot for Heating
Rc Red 24 Volt Hot for Cooling
Y1 Yellow First Stage Cooling
Y2 Blue Second Stage Cooling
G Green
Grey * Energizes Indoor Fan
W1 White Energizes First Stage Heat
W2 Black Energizes Second Stage Heat
O Orange Heat Pump
Reversing Valve
Energized In Cooling
B Brown Heat Pump
Reversing Valve
Energized In Heating
C Brown** 24 Volt Neutral
(Common) leg

 

[Soundguy]

no data plate info on the unit we are installing.. it has been rmoved by someone other than me unfortunately.

thermostat is a mercury bulb style ( non digital ), and other than the ul tag info, and some printed in foil lettering on the circuit board.. there are no model numbers present that I can find.

I know that blue is not hooked up to the thermostat.

soundguy

 

[tommu56]

I dont know if it right but 90% ive seen are wired this way
all 24volt
red hot
green fan on manual
white heat
yellow ac
blue 2nd stage heat


http://www.dr-fix-it.com/ttt/10005.html
tom

 

[Soundguy]

Tomorrow I'm poping opent he inspection panel on both units and will report back what I find.

thanks to tom and box for the replies.

soundguy

 

[Birdhunter1]

On 6 wire T-stat line the blue will sometimes be used for the reversing valve on a heat pump, or as other have stated a 2nd stage heat or cool function. If I were wiring 6 wire (we used 8 on heat pumps just to have the extra 2 in case one went bad) I would do yellow for compressor, blue for reversing valve, white for aux. heat, grn fan and red of course 24 volt power with the brown most likely unused, but that's me and the company I worked for.

 

[Soundguy]

got it working using an 8 wire 'universal' thermostat. took a bit of head scratching.. but brown and blue were unused..

soundguy