Furnace fan + woodstove. What am I overlooking?

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New Member
Nov 12, 2021
Woodstock, VT
Last winter I self-installed an Ambiance Hipster 20/Hearthstone GM60 wood stove, and it’s been a dream. No draft issues. No complaints.

Other than when we’ve been away, we haven’t had to use our oil furnace at all, which is ideal given the trends for heating oil prices.

The one drawback of using the stove as our primary heat source is that while the living room gets hot, some rooms far from the stove tend to get chillier than we’d like, especially overnight.

This is our first house, and I’m an HVAC neophyte, but so far we’ve been doing everything ourselves, so why stop now?

So the other day I put on my thinking cap, did some online searching, popped the Nest off the wall, and discovered that our thermostat had a third wire, not connected to anything. Further Googling told me that this could be a G wire. I went into the basement, took the covers off the furnace, and discovered that it had a spot for a G wire to attach as well.

I connected the third wire, switched the power back on, and the Nest recognized it. Now I can run just the fan … which is notable because the air return/intake for the forced air system is in the same room as the woodstove.

My question is: Is there anything wrong or potentially dangerous about using the fan and ducts from the forced air system to push woodstove-heated air around the house in this way? (Before installing, I made sure the stove would far enough from the register.)

Would love it if anyone can share any expertise.

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Personally I don't think it's major game changer. I use couple of box fans myself instead of furnace fans. Does far better job than our AC/Heat Pump fan. I have setting on thermostat for fan on 100%. Does not seen to do squat in basement. But we run small wall electric heater to keep things 60f. Only Tv and Exercise equipment and other room utility room (Water Tank/Softener). But it does allow the furnace filter to run (Honeywell Electronic Air Cleaner F300E). I put some 20x20 filters on box fans to capture dust with Garbage Gripper Bands. Far enough away the noise is no problem.
If the intake is more than 10 ft away, it's legal.

However, HVAC ducts are often poor in distributing heat from a stove. Are they fully inside the thermal envelope of the home?

Best is as suggested above. Move.the colder.air to the stove room. It'll (necessarily) be replaced by warmer air from the stove room. A fan on the floor,. running low (!) pointing to the stove room is what I would suggest.
My stove is in the basement and I have opened 2 cold air returns in the basement 10 ft from the stove. I also have a hot air outlet at the opposite side of the basement that brings air down. This system works well for me and keeps the rooms upstairs at relatively equal temps and makes the family room in the basement bareable. ( Otherwise it's too warm) Every system is different, however what works well in my home might not in yours. I've been doing g it this way for over 10 years and my furnace fan runs non stop most of the winter. Heats and distributes well
If your ducts are all inside the building envelope then nothing wrong. It may not be the most efficient way generally moving cold air along the floor towards the stove helps set up a convective loop. It can change the temp 5 degrees in out back bedrooms.
If your ducts run through an unheated space, it very likely will not work...I'd say it does not work for way more people than it does...just based on reading of peoples results on here...and it did not work for me.
If your ducts run through an unheated space, it very likely will not work...I'd say it does not work for way more people than it does...just based on reading of peoples results on here...and it did not work for me.
And if the leaks are in the unconditioned space your house is now under negative pressure and sucking in cold outside air.