I am replacing white-rodgers 1E56W-309 thermostat to Honeywell VisionPRO 8000 programmable thermostat. I have 1H/1C system in my house. However, my furnace is used both for heating and cooling. I have read the installation manual for the white-rodgers thermostat and looked at the current thermostat installation. It is a 5-wire 1H/1C heating/cooling system. Now, a 5-wire heating/cooling system for a White-Rodgers 1E56W-309 means there is a transformer for heating and a transformer for cooling. However, because of the single furnace, I am afraid the system could be a single transformer system. Folks, it is possible to have a 2-transformer system with a single furnace?

Thanks in advance,
Eric.

The five independent wires connected to the White-Rodgers 1E56W-309 are: RC, RH, W, G and Y.

Thanks,
Eric.

And what is your question?

No model number with the ending of 309 listed on the WR site

Yes it is possible to have a two transformer system with a single furnace because in some cases the A/C unit has its own transformer making it a two transformer system. They are a bit rare but my system for the main house section does have two transformers.

If you only have one transformer you usually jumper RH-to-RC

Thanks hvac1000. You are really a Pro. The RC and RH terminals are not jumpered, so it is a 2-transformer system. Thanks a million and I shall replace the thermostat this evening and send you an update. Again, thanks.

Eric.

Make sure you turn off the power to the systems before rewiring. It is easy to short the system out when replacing the thermostat. Good luck!

Tim Burke, White-Rodgers.
[email protected]

Thanks for your advice.

Cheers,
Eric.

Folks, I need a little help. On mu current White-Rodgers 1E56W-309 (Obtained from the inside cover of thermostat), the RED wire is attached to RH, black wire to RC, then white wire to W, green wire to G and yellow wire to Y. According to the installation instructions for the Honeywell VisionPRO 8000, the RED wire from the current thermostat, should be connected to C on the Honeywell VisionPRO 8000. Since I have RC and R terminals on the Honeywell VisionPRO 8000, I think it is logical to say that the RED wire should go R in the absence of RH on the Honeywell VisionPRO 8000, since the old thermostat had no C terminal. Please advise. I need to get this off the way before I install Honeywell VisionPRO 8000. Anyway, the terminals on the Honeywell thermostat are: RC, R, W, G, Y and C. The terminals on the White Rodgers 1E56W-309 thermostat are: RC, RH, W, G and Y. There is no jumper between RC and RH. Therefore it is a 5-wire heating/cooling system.


Thanks,
Eric.

Here is your wiring diagram for the old stat.

http://www.white-rodgers.com/wrdhom/..._06_pg0191.pdf


And here.


I am sure you can transpose the wiring with the use of these to compare.
http://www.white-rodgers.com/wrdhom/.../0037-5327.pdf

hvac1000,
You are a genius. I came back and read one of your posts that said that keep it simple and match the existing wiring to your current one. I followed this simple advice and installed the Honeywell VisionPRO 8000 and it is working as I am writing to you.
Both furnace and air conditioner are working and I cannot thank you enough. Wherever you may be, may God bless you immensely. I already had the pdf installation manual for the White-Rodgers 1E56W-309. I needed somebody to confirm the two transformer system with a single furnace, you were the one that was able to explain stuff black and white for me. Again, thanks a million for your good work.

Glad you got it working.