Setting up garage brewery; need safety advice

[forceten]

Hi! First time poster. I'm setting up a small batch homebrewery for my friends and I to brew with in my garage. 28gal pots.. I have a gas line handy, so I'm looking to get the biggest BTU burner possible to have greater control of temperature (and get things up to temperature faster).

That said - it's a garage. It is an enclosed space; CO will build up from big burners, and O2 will vanish quickly from the flames. It's a cinderblock garage with a new garage door coming. In winter months, that door will likely be closed.

There is one window with an opening roughly 35" x 27". I was considering exhaust and intake fans in that opening.

Two things:

1. Where can I find "good enough" intake and exhaust fans - and what does it mean to be "good enough" for safety?

2. Does putting the intake and exhaust next to each other even make sense? Will they cancel each other out? Will I have to cut a hole in the cinder somewhere else?

The garage is attached to the house so there is only one available wall to the outside other than the door wall.

Thank you VERY much for any advice in this matter.

Any other safety tips are appreciated too as we're still selecting parts to buy now.

[Mill Rat]

Thanks for thinking this through. I'd rather read a post than an obit. Yes, you need to ventilate, but you should be able to do that with only one fan. If you make that fan the exhaust, you'll have lower pressure in the garage than in the house, so you won't push fume-laden air into the house.

Both Grainger and McMaster have plenty of fans available. Once you get a handle on the size and fuel for your burner, post that info. hopefully we have an HVAC engineer denizen on this site that can figure out flue gas production and required air changes per hour to give you a target CFM for your fan. You'll need to give the volume, or at least H x W x D of your garage in order to get a meaningful answer.

You're absolutely right that putting intake and exhaust next to each other is a bad idea. You want those as far apart as possible on a building as small as a garage. If they're close together, you'll have an ventilation "short circuit" and the intake will suck right back in whatever you're exhausting, getting you right back to that obit problem.

You may not need to construct a separate intake opening if your exhaust opening is away from the garage door. Just leave the garage door cracked open a few inches above the ground. Voila, you've got your supply opening. If you want to get fancy, put a few ventilation grilles in your garage door, and if you want to get fancier, get the ones with built-in dampers or put hinged dampers that you can close over them.

If I were going to look at this as an industrial installation, I'd wire up a safety circuit that wouldn't let the burner fire until a air flow switch in the exhaust duct confirmed you were moving enough air, but if you're aware enough to ask this question, I think you'll be checking your airflow before you light up the burner anyway.

[zoom6zoom]

If you can rig up an exhaust hood over your burner setup that's ducted to your exhaust, that will help too, in combination with the previously mentioned items.

[forceten]

Thank you for the feedback. Yes, this was a major concern for me right off the bat. I knew that merely keeping the garage door open a crack wouldn't be enough; the combination of the CO build-up as well as the O2 being taken out by high BTU burners seemed to be an issue that HAS to be considered. I'll probably get a monitoring device to monitor the CO levels in the building.

The new garage door is coming soon - but it doesn't really have any provision for grills (it's insulated - the garage is underneath living space, so I wanted to try to keep the floor from being ice cold, as it is now.

But, if exhaust is sufficient combined with the garage door open a few inches, that might do it. I'll have to check with the installer if the automatic opener will allow the door to be only partially open.

I'll take some measurements of the garage itself to get a better handle on the size, and then post back when I have that plus the burners we select.

The help in finding the right system is much appreciated!

Thanks again!

[zoom6zoom]

If the garage is below living space, even if it's insulated itself, it would probably be desirable to insulate the garage ceiling. The garage doesn't need to be as warm as the rest of the house, and this will improve efficiency in your living spaces.

[forceten]

Quick update:

Garage is 23' L x12' W x 7.5' H. The gas pipe will be installed shortly; so I'm not propane, I'm natural gas.

Window is 35"x27" and the rest is cinder.

What is a good BTU to shoot for - I would like to have something powerful; has anyone experience with natural gas burners?

With that information, should I bother with an intake or just always assume garage door cracked open a foot?

And, if anyone can point me in the direction of an exhaust that I can install in the window which will be near/above the burners, that would be very helpful - I don't even know where to start with exhaust fans.

Thank you!!

[Mill Rat]

With enough research, I'll be able to help you out, but it would a lot easier if someone with ventilation design experience would jump in here. Asa sparky, I could handle the electrical questions quite easily, but ventilation isn't my forte.

[forceten]

I've decided on 220,000 BTU natural gas burners.

There will be three of them. Possibly a fourth if necessary, but definitely three.

So 660,000-880,000 BTU in the space described above.

I'm still not sure what to buy for exhaust as well as intake.

Thanks for any feedback (sorry about the time delay -- things have been slow)

[ClaudiusB]

I brew in the garage with piped in propane and a 3" forced fresh air supply to each of my burners.
Burner range from 75,000 BTU- 300,000 BTU.
Garage door is always open, no vent hood required.

What is a good BTU to shoot for - I would like to have something powerful

100,000 BTU for 28 gl , 150° F temp rise in 0.5 h is enough.
If your heat transfer efficiency is only 50% you need a 200,000 BTU burner.
; has anyone experience with natural gas burners?
Why?
Burners are burners.
I use both Low & High pressure propane burners.

Cheers,
ClaudiusB

[MrNate]

Originally posted by ClaudiusB
Why?
Burners are burners.
I use both Low & High pressure propane burners.

Cheers,
ClaudiusB

Because NG is cheaper than LP. Around here, anyway, but I'd imagine it's the same in TX*. Also, no worries about running out. It's much more convenient.


* I forgot, you're in El Paso. Maybe not.

[wortchillergoal]

I am not sure about sizing an exhaust fan for a room. I do know how to size a fan connected to hood. The formula is

LxWx100=cfm of fan. The L being the length of hood and W the width(or depth from wall).

[ClaudiusB]

Because NG is cheaper than LP. Around here, anyway, but I'd imagine it's the same in TX*.

OK!
I was not looking at cost, next time.
As a technical guy I looked only at the hardware.
Also, no worries about running out. It's much more convenient.
You are winning again:D
Good planning by the brewer, no running out of gas.
I have a few tanks on hand.
In El Paso it's not legal to use propane inside if NG is within 1000' from the house. But the law doesn't address brewing.
The law also states it's illegal to drink and drive.
I drink before I drive.
I am not sure about sizing an exhaust fan for a room.
If you have volume of 200 ft³ of air, and you plan on replacing the
air during an one hour period you need a 3.33 ft³/ min fan.
A 200 ft³/ min fan requires only one minute run time per hour.
Which method is better depends on the application.

Cheers,
ClaudiusB

[MrNate]

Originally posted by ClaudiusB
Good planning by the brewer, no running out of gas.


In theory, there's no difference between Theory and Practice. In practice, there is. :D

[Henway]

I am doing something similar, but will have only one NG 220K burner.

Someone mentioned forced intake air (but it was for Propane). Is there a reason for this? Is the venting for the burner or for the humans brewing nearby?

I was just going to have it vented through a normal stove exhaust fan with a 6" stack out through the roof and then I could have an open window or open the door to the adjacent garage (and the garage space leaks air like a sieve--horizontal sliding doors).