Progammable Blower Timer

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HomeinPA

Minister of Fire
Jan 4, 2018
510
Central PA
Ok, I need some help this time and hopefully someone on here knows what I'm trying to accomplish.

We heat our house with a Quadrafire 5700 in our basement. I had a 5x5 hood installed over it and we ran duct work from the hood to the cold air return duct to the furnace. At night I flip the blower fan on and let it run on low speed through the night to push more warm air upstairs and even the heat out throughout the house on these really cold nights. What I'm looking for is some type of programmable timer that I can wire into the old furnace that will cycle the blower for 10 minutes or so every half hour so I can set it and forget it. Has anyone else undertaken something like this???

I've found a number of programmable timers but they all say they only have the ability to do 7 different cycles. I can't tell if that's per day or per week..... I need a 24 hour programmable deal. I don't know if I'm making this harder than it needs to be or what. Any thoughts out there?
 
So, you know that this type of installation is against mechanical code, right? Why this setup instead of a proper add-on wood furnace? There are devices to cycle the furnace available.
 
So, you know that this type of installation is against mechanical code, right? Why this setup instead of a proper add-on wood furnace? There are devices to cycle the furnace available.
No I don't. Why would it be? What particular section are you referencing? The gas is completely disconnected and it's simply a circulation blower that happens to be 15 feet away from the stove. I'm just using the existing duct work to distribute warm air around the house.

What are these devices that you refer to?
 
I am heading out soon, but have posted the code chapter and verse previously. The intent of the code is to prevent any noxious gases to be pulled into the hvac system. Return air must be at least 10 ft from the stove for this reason. Another concern is pulling combustion air away from the stove. A wood furnace is properly designed to addressed these issues.
 
Do you have a way to slow down the furnace fan? The problem I ran into was the speed of the fan. A furnace takes 1200 degree fire box and runs it through ducts and it comes out at 70 degrees. All I ever did was manage to make the whole house equally cold. I also tried an inline duct fan. Not enough volume to overcome the ductwork and would just rattle once the air backed up.
 
No I don't. Why would it be? What particular section are you referencing? The gas is completely disconnected and it's simply a circulation blower that happens to be 15 feet away from the stove. I'm just using the existing duct work to distribute warm air around the house.

What are these devices that you refer to?
It is against code cold air returns must be a minimum 10' from the stove not directly over it. That being said we see allot of installs like it here and they can work quite well.
 
It is against code cold air returns must be a minimum 10' from the stove not directly over it. That being said we see allot of installs like it here and they can work quite well.
Yeah, I guess I should have looked into that beforehand but never had any experience with it and would never have thought it to be an issue. It has made a huge difference in the 2nd floor temperature and has had zero effect on the stove. For what that's worth. The setup we have now has the blower circulating for 15 minutes on after 30 minutes off all day long.
 
The gas is completely disconnected and it's simply a circulation blower that happens to be 15 feet away from the stove. I'm just using the existing duct work to distribute warm air around the house.
Was there a point to your post or did something go wrong?
 
This is similar to what we have, although ours was cheaper: https://www.amazon.com/dp/B00FLZEQH2/?tag=hearthamazon-20

Honeywell has a Fan Circulation setting on some of their programmable thermostats. Mine is an older model but their instructions say it cycles the blower approximately 35% of the time. I think my instructions say 2-12 minute cycles per hour but I don't have them in front of me to reference. The thermostat is 24/7 programmable so you can set the Circulation setting in any of the programmable time periods.

This works well in our house as our cold air returns are in the living room where the stove is also located.

I'm not clear though, is your furnace still functional or are you only using the blower? If not this may be overkill as you would never use the actual thermostat functions. There may be a cheaper model available with the same fan function though.
 
It's safer, but not necessarily as effective to suck the cold air from the cold area and dump it into the stove room.
Pulling air from the stove room, could potentially depressurize the room and cause a down draft.