Venting Heat into Furnace Duct

Hello everyone. I am redesigning my grow room, and I'm considering venting my grow rooms heat into my gas furnace. The idea is that heat will distribute throughout the house. I have a 900 CFM fan that will will be pumping into the system, and I have a few concerns. I've attached a picture as well for some clarity.

1. Where should I tap into the furnace system so it provides heat (I labeled the picture for ease)?

2. Will it be necessary to turn the furnace fan on at all times (no heat) to help push the air upward more? (I'm concerned that the heat will just blow through and out the front of the furnace otherwise).


I have a carbon monoxide detector I just bought just in case as well.




2000 watt grow room.

Also, I was hoping to use it heat the house at night this winter.

What about smell? How you going to control that since it's in every room.

Your furnace takes air in from an air intake somewhere in the house, that is then ducted to a filter, then into the furnace and back around the house. You want to feed in just before the filter. Do not cut anything permanent, rather build out of cardboard, or if you have the tools and time out of sheet metal and tape it to the existing duct. (remove the filter door and leave off, replacing with your diy ducting from your room, then when needs to be put back together you just have to remove tape and put the door back.)
As far as the furnace needing to be on, it will help, but i don't believe it will be needed, you will just get heat out of your intake vent also, no biggie. Only issue i see is if the house gets too hot. But thats a deal with it when you come to it prob.

b-rad said:

What about smell? How you going to control that since it's in every room.

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You will need a charcoal filter for sure to clean the air before you vent to the return air duct which draw's air in to the furnace (B) and then through your home.

If you run this during the winter month's you will not require use of the humidifier if you have one as your plants will provide humidity (remove it and you have an access point to vent to).