Venting out chimney.

Bomixius

Bomixius

Active Member
So I was in my basement checking out where I might put a new tent, and my house has an old style chimney. The kind of chimney that goes from basement all the way too the roof, and is where the current furnace vent runs.

I was wondering how people would think it would work if I put a "y" in the furnace vent line and used the chimney to vent my grow room. It would give the exhaust say 30+ ft of line to dissipate any smell and it would release the exhaust 25+ feet above the road or sidewalk.
 
droopy107

droopy107

Well-Known Member
If the chimney is still in use by your furnace, you would be taking a serious risk by hooking up to it with a vent fan. Because of the pressure that the fan will create, you can easily cause the flue gas from the furnace to be pushed back into your house instead of drawn out the chimney, resulting in carbon monoxide poisoning.

A chimney like that is designed to work under much different conditions than you will have with a high volume fan pushing into it. Risky business.
 
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DemonTrich

DemonTrich

Well-Known Member
+100000
DO NOT do what you had planned. it can and will backdraft back down your chimney stack and blow out your gas furnace and water heater pilots. and possibly cause an explosion.

I tried to tap into my dryer duct. the exhaust was not allowing my dryer air to go out the same ducting from the Y. the dryer air was stopped at the Y and was backdrafting back into my dryer and venting it back into my house. I ended up running a new separate grow exhaust and no more issues.
 
ttystikk

ttystikk

Well-Known Member
OR, add your exhaust fan downstream of the furnace flue as well, and put it on a thermostat; anytime temps climb over 80f, the fan runs. This draws any flue gases out of the house as well as ventilating your grow op.
 
uzerneims

uzerneims

Well-Known Member
Dunno man! One SWIM grow op was with running everything in chimney, yes they are designed for constant airflow, but in same time i got paranoid, because neighbours could feel wind blowing :D
 
DemonTrich

DemonTrich

Well-Known Member
ok, try thinking of it like this. the Y is a freeway, one side of the Y is the fast lane with cars speeding (grow room exhaust air flow that's running 24/7), now the other part of the Y is merging traffic onto the freeway (furnace/water heater exhaust). the freeway is moving is such a speed, its NOT allowing the slower moving traffic (aka furnace/water heater exhaust gasses) to "merge" in with "traffic" (air flow). this will cause the furnace/water heater side of the exhaust gasses to be backed up into the exhaust stream of its part of the Y. this can and WILL cause such gasses to get backed up in the system, blowing out the pilot and filling up your house with deadly co2.

this was explained to me by numerous heating cooling experts.

so good luck, and if you do plan on running it your way, please invest in 2-3 co2 meters . at least you will have a little heads up by some beeping before you pass out and possibly die from co2 suffocation.
 
ttystikk

ttystikk

Well-Known Member
DemonTrich said:
ok, try thinking of it like this. the Y is a freeway, one side of the Y is the fast lane with cars speeding (grow room exhaust air flow that's running 24/7), now the other part of the Y is merging traffic onto the freeway (furnace/water heater exhaust). the freeway is moving is such a speed, its NOT allowing the slower moving traffic (aka furnace/water heater exhaust gasses) to "merge" in with "traffic" (air flow). this will cause the furnace/water heater side of the exhaust gasses to be backed up into the exhaust stream of its part of the Y. this can and WILL cause such gasses to get backed up in the system, blowing out the pilot and filling up your house with deadly co2.

this was explained to me by numerous heating cooling experts.

so good luck, and if you do plan on running it your way, please invest in 2-3 co2 meters . at least you will have a little heads up by some beeping before you pass out and possibly die from co2 suffocation.
Click to expand...
You aren't paying attention; place the exhaust helper fan DOWNSTREAM of the Y- no problem.
 
skunkd0c

skunkd0c

Well-Known Member
it would have to be a very thin chimney (small air volume) and a very powerful fan to cause so much positive pressure
that their would be a back-draft ?
 
H R Puff N Stuff

H R Puff N Stuff

Well-Known Member
down stream or not you shouldnt do it if they where both forced air (by fan )or both convection air (by heat or lighter than air gases ) then yes you have one of each so no. not to say that if there is enough space you can insert a 3" vent pipe in the chimney there by seperating the two good luck but do not use both in chimney without seperating its a recipe for carbon monoxide poisoning or fire. i am a lic. contractor
 
DemonTrich

DemonTrich

Well-Known Member
downstream upstream, it doesn't matter!!!! airflow doesn't care where you try at make a junction.


peace out

I hope things work out for ya. im done with trying to help people out this morning.
 
Bomixius

Bomixius

Active Member
Thanks everyone, I have a duct out the back of my house, I was just curious if this would work as well. I think as most said it would not be a sound idea. I will not do this, thanks.
 
T

Tn Herbs

New Member
[QUOTBomixius, post: 10847619, member: 881935"]Thanks everyone, I have a duct out the back of my house, I was just curious if this would work as well. I think as most said it would not be a sound idea. I will not do this, thanks.[/QUOTE]
Good mornin' y'all. I was jus' wonderin' if a little of that co2 couldn't be ran into the grow for the plants?
 
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