chinmey venting questions

Masonic72

Well-Known Member
At the bottom of the chimney in the basement is a square hole ,I assume its a draft hole for the chimney.
The water heater is the only thing using the chimney . the water heater vent is about 5ft up the chimney from the floor . if I used this draft hole at the bottom of my chimney. would this cause a backdraft on the water heater? can I just stick my duct into the hole or should I try and run the duct up a few feet in the chunmey?
Thanks
 

kingtitan

Well-Known Member
is there a damper on the water heater duct where it exits in the chimney? Im no HVAC but there should be one to stop backdrafts. I wouldnt cut off the passive intake on the chimney. What kind of chimney we talking about? old house with the brick that santa comes down or a new house with just metal duct made for venting burned fuel for furnace and heater? the latter will have less volume capacity as it was not designed to be venting at pressure.
 

Masonic72

Well-Known Member
its brick older house 1940's and just a water heater hooked to the chimney . metal duct work from the water heater to chimney that's it. furnace is vent out the side of the house and doesn't use the chimney at all No dampener on the water heater its ducted straight to the chimney. ill look and see if I can see up the chinmey
 
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kingtitan

Well-Known Member
I don't want to give any advice on this matter as I am not really sure and the last thing we would want is a backdraft pushing carbon monoxide into your home by putting force on it. CAn you vent into the basement and just let it passively get taken out? how much CFM are we talking about? I have seen large grow houses duct through brick chimneys.
 

Masonic72

Well-Known Member
its a 4in 170cfm ducting is what ill be using about 7ft or less ducting to the chimney . 1 maybe 2 plants . 4x4 .looked at chimney its open all the way up . This what im thinking . I wont be sealing the bottom of chimney just adding the 4in duct in the hole and blow up the chimney ,I do agree about the clean out , however only wood stoves put off ash or coal my house has used neither . and the furnace doesn't use the chimney my furnace is exhausted like a clothes dryer out the side of the house.. i can experiment with it today .just want to make sure the water heater doesn't backdraft
thanks guys i really hope i can get this to work .
 
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thumper60

Well-Known Member
its a 4in 170cfm ducting is what ill be using about 7ft or less ducting to the chimney . 1 maybe 2 plants . 4x4 .looked at chimney its open all the way up . This what im thinking . I wont be sealing the bottom of chimney just adding the 4in duct in the hole and blow up the chimney ,I do agree about the clean out , however only wood stoves put off ash or coal my house has used neither . and the furnace doesn't use the chimney my furnace is exhausted like a clothes dryer out the side of the house.. i can experiment with it today .just want to make sure the water heater doesn't backdraft
thanks guys i really hope i can get this to work .
how big is flue in chim?u want the wh vent below forced air
 

Lite

Well-Known Member
youre better off running it through a carbon filter and just venting it somewhere inside. Basement temps are constant enough to not worry about where you are exhausting it...
 

brewbeer

Well-Known Member
If you vent through the chimney, you could cause the water heater exhaust to discharge into the basement.
 

Lite

Well-Known Member
exactly, if its a power vented exhaust it will put the chimney in a positive pressure and cause the flu gas from the water heater to go into the house. Very true.
 
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