Cold Air Return From Existing Run

Finally hooked up my cold air return to the blowers from our existing return air pipes on the furance. Seems to work, did the match test and the smoke was drawn down thru the grate....

Made my flange for the blowers from a 5" elbow, just cut tabs and bent back and used existing screws. I marked where the screws were, and just cut slots to slide under the screws. Used 5" run from both fans and then into a TEE up to 6" to tie back to the furnance duct work. Rectangle Floor adapter to existing furnance cold air return.

Did it make any difference?. My pioneer is located in the kitchen and my furnace's cold air return is located right below it in the basement. I was thinking of running 3" single wall vent pipe or drier hose from my combustion blower to my cold air return of my furnace. Since I don't use the furnace anymore and its 2 years old maybe I could get some sort of use out of it.

It would be easier for me to connect to the cold air return than trying to run vent piping to the outside because of where my pioneer is.

Hello Smith 10210, By connecting the combustion fan to your cold air return, you really haven't accomplished anything. You would see difference if you hooked your cold air return to the heat distribution fan, this would creat better heat circulation in your house.

Greg L

In you remember how mine was piped upstairs, my heat output pipe actually ties into the main heat duct from the furnace, the cold air returns are about 10-12' away from where the heat comes up, it seems to circulate much better.

I was just thinking it would be better to draw some cold air to the combustion fan from either the cold air return or the basement in general since I don't heat the basement and don't use the furnace and it would better than sucking the warm air from the kitchen where the stove is located. So it would be better just to run it outside for fresh air I take it?. What changes would I notice as far as the stove performance? Less coal consumption more heat etc?.

The combustion fan is feeding the fire and all the air going through the combustion fan goes up the chimney. If you can feed the combustion fan with outside air, you will no longer be putting a slight vacuum on your house and this will reduce the infiltration of cold outside air into your house.

It won't make the coal burn hotter, but your house won't be pulling in cold air through every crack and crevice around windows and doors.

Greg L

LsFarm wrote:The combustion fan is feeding the fire and all the air going through the combustion fan goes up the chimney. If you can feed the combustion fan with outside air, you will no longer be putting a slight vacuum on your house and this will reduce the infiltration of cold outside air into your house.

It won't make the coal burn hotter, but your house won't be pulling in cold air through every crack and crevice around windows and doors.

Greg L

I see makes sense. I guess I'll run it outside than. I was hoping to just use the cold air return. Thanks for your help..

Does anyone know if 12' of 3" vent piping with 2 90 degree turns would be sufficient or would I have to run 4" vent pipe. It would be a straight from the stove than a 90 than a short straight down to the basement than another 90 than about 9' straight to the wall and outside with a cap.. I was planning on using B vent or pvc not to sure.

For intake combustion air, you don't need B Vent? isn't that double wall?
It can be single wall galvanized or PVC, I wouldn't make it any smaller than the size of the intake on the blower.

I think its single wall. What you use for hot water tanks... I'll stick with 3" than hopefully that will do if not I'll have to buy a 4" hole saw than which are pricey.. Thanks for the speedy reply

smith10210 wrote: I'll stick with 3" than hopefully that will do

I've 3" pipe and have not a problem with it on my Alaska, the inlet is 3" at the fan as well.