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runnerxc
12-01-2011, 08:04 PM
Hey all,
This is a follow up to my last post: Link (http://hvac-talk.com/vbb/showthread.php?p=11785472#post11785472)

To solve my problem, I want to install a temperature control switch on the plenum of my furnace to switch the fan on at the high limit temperature and then switch it off when it reaches the low limit. This will work great because I can run the wood furnace fan continuously and when the plenum of the furnace gets warm, the gas furnace blower will kick on to assist.

Now, the question I have is how to wire this? The manual for my furnace is here (http://www.allreds.net/WS2/docs/arm/g2d95ct_manual.pdf) and states:
"To engage the continuous blower operation, place the fan switch on the thermostat into the ON position. A call for fan from the thermostat closes R to G on the control board. The control waits for a 1-second thermostat debounce delay before responding to the call for fan by ramping the circulating blower up to 50% of the cooling speed. When the call for continuous fan is satisfied, the control immediately ramps down the circulating blower."

Does that mean I could use a simple snap disk temperature controller (which I have) and just connect the R and G on the control board to it? That way, when the high is reached, is closes the R to G and that should engage the fan, right? Is it really that easy? Any other/better/easier ways to accomplish this? Any help would be great.
Thanks.

skippedover
12-01-2011, 08:23 PM
Awfully sorry friend but I can't condone a layman doing any wiring on the furnace. If you let out the magic smoke, you can harm the equipment. If you get the wrong wire or wires, you could let the magic out of your own self. I'd recommend contacting a qualified company to do the wiring for you.

beenthere
12-01-2011, 09:04 PM
That method of wiring, will probably also turn on your A/C.

runnerxc
12-01-2011, 09:10 PM
I just thought I would come here first and see if anyone could help me out...I didn't know how hard it would be. It doesn't seem like too hard of a thing to accomplish...

motoguy128
12-02-2011, 10:27 AM
Why not just run in constant fan all winter. It sounds like you have a vairable speed blower. It shouldn't use more than 100 Watts in constant fan speed. Is the wood stove connected into the furnace ductwork?

Its' also possible to just use a thermostat to cycle on the fan only. It could be mounted in the home or ther are thermostats made to be mounted to or in ductwork.

As mentioned above... probably worth having a pro wire this up.