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cali · Aug 29, 2006, 07:10 PM

Hi!

I've just removed my Honeywell Thermostat and am trying to replace it with a Noma programmable tstat... but am having problems with the wiring. There are 5 wires coming out of the wall - Green, Black, Orange, Red and White, and only 4 posts on the Noma tstat (Green, Red, Yellow and White). Can't seem to get the right combintation! (The old Honeywell shows RH, G, R, Y and W if that helps... ) Suggestions greatly appreciated! Thanks! Cali :o)

letmetellu · Aug 29, 2006, 09:05 PM

If you do not have a heat pump, which that is what it sounds like, the wiring should be as follows: Red should go to the R. White should go to the W. Green should go to the G. now you are going to have to do some checking. Either the black or the orange is to go to the Y. To find this out you need to look at the circuit board in the furnace or air handler which ever you have. You will find on the board the same letters you have on the tstat. On the C you should have one wire that goes to the AC unit out side, on the Y you should have two wires one goes to the unit outside and the other should be either the black or the orange from the tsat. So use this color to connect to the Y on the new tsat. If all else is normal and you have not blown a fuse things should work. Let me know what happens.

cali · Aug 30, 2006, 06:05 AM

I'm not at home now, but if I recall correctly, the black was going to the orange and also on it's own in the furnace circuit board... Does that make sense?

cali · Aug 30, 2006, 05:17 PM

Thanks 'letmetellu' for your reply... It's all good now, had an electrician friend stop by and fix 'er up for me!