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General Category => Equipment and Software => Topic started by: blatz on July 15, 2011, 02:59:27 PM

Title: Placement of Vent for Condensate Hood
Post by: blatz on July 15, 2011, 02:59:27 PM
Hey all

I'm finally at the point where I need to position my condensate hood and venting. 

The hood is 6' and has an 8" round exhaust riser on the top to which I will reduce to 6" and hook up a vortex fan. 

My question is:  would it be better to vent out of the room above the hood which would have the least amount of distance travelled or vent out the perpendicular wall, which would allow me to slope the ducting a bit to prevent water from forming and dripping back in.

My other concern is I heard, though have had trouble confirming that if I need a make up air vent (which I may not - our a/c people are calculating the CFM loss vs A/C) it cannot be on the same wall as the vent - I would think a makeup air vent would be best served directly above the kettles in between the kettles and the hood.

Thoughts/advice/comments appreciated.
Title: Re: Placement of Vent for Condensate Hood
Post by: Jimmy K on July 15, 2011, 04:30:48 PM
Propane? Then your venting two things - moisture and CO2 (exhaust from the burners). The second is much more important the the first as it can kill you. If you're trying to vent the whole room, then the opposite wall is correct. But for just the brewery space you could change that. Still, I'd position the make up vent below the burners.
Title: Re: Placement of Vent for Condensate Hood
Post by: Slowbrew on July 15, 2011, 04:39:52 PM
Propane? Then your venting two things - moisture and CO2 (exhaust from the burners). The second is much more important the the first as it can kill you. If you're trying to vent the whole room, then the opposite wall is correct. But for just the brewery space you could change that. Still, I'd position the make up vent below the burners.

Just to make sure we're all clear.  It's not CO2 he needs to worry about it's CO (dioxide verses Monoxide).  Too much C02 can be a problem but it doesn't take a lot of CO to become a very big problem.

Other than that, I agree with you advice.

Paul
Title: Re: Placement of Vent for Condensate Hood
Post by: Jimmy K on July 15, 2011, 05:00:12 PM
That right. I was thinking CO2 buildup leads to low O2, which leads to CO buildup. But that's my convoluted thinking. CO that is really the problem.
Title: Re: Placement of Vent for Condensate Hood
Post by: blatz on July 15, 2011, 05:01:56 PM
Electric elements not propane
Title: Re: Placement of Vent for Condensate Hood
Post by: Jimmy K on July 15, 2011, 05:04:30 PM
Then I don't think it would matter much where the make-up vent is.
Title: Re: Placement of Vent for Condensate Hood
Post by: blatz on July 15, 2011, 05:18:40 PM
Cool.  thanks. 
Title: Re: Placement of Vent for Condensate Hood
Post by: ckpash88 on July 15, 2011, 05:26:44 PM
I would slope the exhuast pipe bc you have to worry about condensation and if you are in a area that gets cold it could freeze and cause alot of damage. When we vent furnace we have a aggressive slope to avoid condensation and the pipes from freezing
Title: Re: Placement of Vent for Condensate Hood
Post by: tom on July 15, 2011, 05:35:08 PM
What slope do you recommend?
Title: Re: Placement of Vent for Condensate Hood
Post by: ckpash88 on July 15, 2011, 05:42:32 PM
It really all depends on code when I install furnace each city and county is different. But it's normally 1-3 degrees sloped back to the furncae.
Title: Re: Placement of Vent for Condensate Hood
Post by: ckpash88 on July 15, 2011, 05:49:17 PM
1-3 sounds right but another way to look at it is for every foot you go out raise it a 1/4 of a inch for example a 8 foot pipe the end that going outside is 2 inches higher the then the source
Title: Re: Placement of Vent for Condensate Hood
Post by: blatz on July 15, 2011, 05:51:30 PM
hmm - for this application, I would imagine I would want it sloped downward at the exit/wall so that water condensate can drip out the vent, rather than running back into the fan or even the hood opening itself?
Title: Re: Placement of Vent for Condensate Hood
Post by: ckpash88 on July 15, 2011, 06:04:06 PM
Yeah probably I am speaking from experience with furnace but they have built in drains. The theory is that the condensation stays in the condition air space and does not freeze and cause a blockage in the pipe.
Title: Re: Placement of Vent for Condensate Hood
Post by: blatz on July 15, 2011, 06:18:31 PM
believe me - I will never, ever have a problem with freezing.  ;)
Title: Re: Placement of Vent for Condensate Hood
Post by: ckpash88 on July 15, 2011, 06:22:23 PM
Then I would slope it out and away. I live in Minnesota we get cold lol
Title: Re: Placement of Vent for Condensate Hood
Post by: tom on July 16, 2011, 01:00:12 AM
The hood is 6' and has an 8" round exhaust riser on the top to which I will reduce to 6" and hook up a vortex fan. 
Why are you reducing it?  8" diameter is almost twice a large as 6".
Title: Re: Placement of Vent for Condensate Hood
Post by: Hokerer on July 16, 2011, 02:11:34 AM
The hood is 6' and has an 8" round exhaust riser on the top to which I will reduce to 6" and hook up a vortex fan. 
Why are you reducing it?  8" diameter is almost twice a large as 6".

My guess would be because his vortex fan is 6"
Title: Re: Placement of Vent for Condensate Hood
Post by: blatz on July 16, 2011, 02:06:41 PM
The hood is 6' and has an 8" round exhaust riser on the top to which I will reduce to 6" and hook up a vortex fan. 
Why are you reducing it?  8" diameter is almost twice a large as 6".

My guess would be because his vortex fan is 6"

good question tom - but yes, I've decided on the 6" vortex fan since it has a max CFM of 449 (which I am adding a control to lower when full power not needed) but the 8" has a max of 747 CFM which is considerably higher than what I need.  I can of course mod it with a controller - I'm not dead set yet, but being that the room is A/C'd, I want to be cautious of how much air is being sucked out.
Title: Re: Placement of Vent for Condensate Hood
Post by: Thirsty_Monk on July 16, 2011, 02:53:12 PM
Just a speculation but if you have enough air flow you should not form condensation.
What fan are you using?
I have 6" pipe and 250 CFM and that is not enough.
Title: Re: Placement of Vent for Condensate Hood
Post by: Kit B on July 22, 2011, 02:50:44 PM
Just a speculation but if you have enough air flow you should not form condensation.
What fan are you using?
I have 6" pipe and 250 CFM and that is not enough.

The condensation will be from steam exiting the kettles.
I believe he absolutely will have condensation.
Title: Re: Placement of Vent for Condensate Hood
Post by: 1vertical on July 25, 2011, 02:32:01 PM
I had a Jennaire Stove with indoor grill I vented it out the crawlspace to the vertical
exterior wall.  I neglected to use flashing on that wall, Long story short Water
made it's way in around that 6 inch vent pipe and rotted 2 joist ends and about 3-4 foot
of Sill Plate...so make sure you use flashing around those exit ports on your vertical walls.
Title: Re: Placement of Vent for Condensate Hood
Post by: ntabb on July 25, 2011, 02:44:30 PM
I recently built a hood and used the Vortex 6" fan and it worked great. Humidy didn't raise 1% and you couldn't even smelled that I brewed beer in the basement when I was done. My wife was very happy about that. The only thing I would suggest is drilling a hole in the bottom of the fan for it to drain. It will drip constantly during the boil.