Blower fan source air from furnace

[stihltheone]

He is the latest project
I am going to cut into the gas furnace return air plenum, install a really cool squirrell cage blower in the crawl space, duct with 4 inch pvc throught the bottom kitchen cupboard, through a wall and over to the stove,where then I will remove the factory noise makers and build a plenum for the pressuerized, and filtered air from the return of the furnace. I will also create a very desirable convection air flow to the rest of the house this way. What do ya think if this? The blower is a really nice industrial 100% duty cycle, 450 cfm unit. I was at the right place at the right time. This whould be a nearly silent set up with the benifit of filtered air, and hopefully end te cold air leaching up from the vents. My gas furnace only runs when is is -20 or so and then not even much.

 

[LLigetfa]

What you describe is illegal to do in Canada. The air handling system of a gas furnace cannot/must not be tied to any other heating system.

What I did was build a blower system down in my crawlspace which by code is conditioned plenum space. I have two furnace type air filters in the housing and I duct cool filtered air up to my fireplace. The air returns to the crawlspace at the far end of the house. This warmed air stratifies in the crawlspace, warmer on top warming the underside of the floor above, cooler down on the concrete picked up by the blower and recirculated.

Works a charm. Noise kept to a minimum and air filtered through a quality 3M Filtrete filter. The warmed floors result in very even heat throughout the house, almost like in-floor heating.

 

[madison]

I would hazard a guess that this is not to code anywhere. The one risk i see off the top of my head, is the added blower could, under bad circumstances, pull air from the furnace (that should be going up it's exhaust), and not the rest of the house, risking CO distribution to the home.

And when the furnace does come on, I would hazard a guess that the HAVC would be imbalanced.

Not worth the cost, risks, and little added benefit IMHO.

 

[begreen]

Code in US is that there can not be a return air vent within 10 ft of the wood burning appliance. Code aside, blowing 450cfm through a 4" pipe is not going to be quiet at all. Many fans are not going to be happy with that high static pressure.