Originally Posted by #CARRIERMAN
I would reccomend goin to the furnace and finding out how it is wired. mdshunk could be right the thing you are calling a thermostat that you removed could be a dc interface. The thing you saw called an add a wire, goes to the g circuit and allows the a/c switch to operate the blower circuit. If you have a 24 volt circuit for your thermostat you will need to leave the rc-rh jumper in. I will give you the termanology so you understand what those letters mean.
RC= 24 VOLT HOT, COOLING CIRCUIT
RH= 24 VOLT HOT, HEATING CIRCUIT
W= 24 VOLT OUTPUT, HEAT
Y= 24 VOLT OUTPUT, COOL
G= 24 VOLT OUTPUT, BLOWER
C= 24 VOLT COMMON OR NEUTRAL, NOT TO BE COFUSED WITH GROUND.
Let me know if you need any more help
Judging from your posts it sounds as if you know a thing or two about thermostats so I'm hoping you can help me out. I am trying to change my existing thermostat (Weathertron) for our heat pump with a Noma THM303M. The wires that are attached to the existing thermostat are labelled as follows: R, G, Y, X2, B, W, F, O
There is a wire running from X2 to W in addition to the wire that is going to X2. This wire does not come from the wall but appears to connect X2 to W (hopefully that makes sense). The connections for the Noma unit are as you have specified them in your 11:40 am post.
Any help you can provide would be appreciated!