Electric Brewery - Ventilation Question

I am in the process of building a clone of Kal's electric brewery and am slightly stumped on how to best ventilate my set up out of the glass block window I have access to in my future brew room. Here is the window as it stands today:



My original idea was to use the same size fan as Kal, the Vortex VTX600 running six inch diameter rigid metal ducting to the window before going through a short 6" to 4" reducer to fit over a very common dryer vent style glass block replacement which would be located in the middle row on the far left. My original idea for make up air was going to be to install another dryer vent slot, without the plastic louvers, in that same row but on the far right square, leaving me with about 16" (I think the blocks are 8" square) or so between the exhaust and make-up inlet.

My first question would be for those of you with exhaust systems, is this enough distance between the exhaust and make up air inlet? Or will I end up just sucking back in the same hot, humid air I am venting outside?

My second question is, what about a solution that involves a vent window next to the dryer vent as shown below? Obviously this makes the gap effectively zero between exhaust and make up air inlet, but these vents are in my other windows in the basement and would most likely allow a better flow of make up air into my brew room.



Thoughts?

I used a 8 inch-in-line duct fan(over BK)between some ducting to a vent grill outside, preliminary tests seem to work good! Brewing tomorrow and that will be the test!

Why wouldn't you just open one of the other windows for the make up air? I don't see why they would need to be next to each other, the room air will equalize.

I guess you make a good point, the only thing I was worried about was that this room in my basement is closed off by walls and a door from the rest of the basement, including my two other glass block windows with the vents in them as seen in the picture above. Would I definitely want to keep the door to this room propped open if I were to open the other windows for male up air?

I guess another reason to have the exhaust and make up air in the same window would be to minimize the wasted energy in the winter/summer. By being able to close off my brew room from the rest of the basement I would be only allowing cold/hot air in one 8 by 8 room and saving on some wasted energy.

Anyone tried a similar set up out there with the exhaust and make up air so close and had problems?? Thanks for all the responses guys.

If your house is all electric I'm not sure I would worry about make up air. If you have a gas furnace and water heater then the make up air will keep from sucking in carbon monoxide.

That's the catch 22 here, I have a high efficiency gas furnace and an electric water heater. Now I know that my furnace has a PVC exhaust and intake through the side of the house, is that intake completely sealed? If that is the case then technically the furnace isn't using any of the house's internal air for combustion and it's truly coming from outside the home. This would make the need for make up air much less in my case.

My second question is to all of you here, is there any difference between using PVC ductwork versus metal ductwork besides a small up tick in price? I ask because my furnace exhaust is PVC and is so because it easy allows condensation to drain back towards the furnace. I am seriously leaning towards using 6" PVC for my exhaust leading to an exit pipe outside. Any thoughts here?

I have my exhaust vent about 2 feet away from a basement window like yours, and when I used that window for makeup air, the vented air recirculated through the window when the wind was in the wrong direction. Now I use a window in an adjacent room for makeup air.

You want to have the makeup air source free-flowing enough that air isn't drawn in through other holes in your house, like fireplaces or kitchen vents.

One difference between the PVC and metal ducting will be it's permanence. If you use metal ducts you can un-tape and disassemble them to change the configuration if ever you need to, but with PVC that is cemented together, what you build is permanent. I like to be able to disassemble things easily for those times 3 years from now when what seemed like a good idea at the time no longer is a good idea.

Thanks for the insight. I figured that the re-circulation would be an issue having the fresh air intake and exhaust vent so close to each other. Obviously as you are exhausting you hit and humid air a large portion of it could get pulled right back in the room via the air inlet.

Also great point on the permanence factor. It really didn't cross my mind at all until you mentioned it but if I go glueing the PVC like I was planning to, when I want and/or need changes it would require cutting the pipe to remove. PVC usually is a snug fit without the glue but I am assuming that might cause issues when pulling pressurized air through it in a duct situation and even the fan itself could vibrate the pieces apart.

Could you maybe used a silicone sealant to hold the pipes in place instead of glue? That would maybe give you the hold you need but ability to easily pull the pipes apart (relatively) if changes need to be made. I have a drawing of some plan ideas I will scan and upload later to give you all a chance to sound off on my plans.

Thanks as always guys and keep the replies/ideas coming!

So I had a chance to sit down and sketch out some simple ideas for my brew room ventilation. Here is what I cam up with:



So here's the general idea:

The layout on the left is a Top View of the room with the brew stand under the vent hood against the back wall of the room. To the right of the stand and hood will be the control panel mounted on the wall. Out of the front of the hood, on the far right side, will be a 6" PVC exhaust pipe that will extend straight outward then have a 90 degree elbow turning towards the glass block window. Just before the window I will have the Vortex VTX600 fan that Kal uses, pulling vent air through the tube. Immediately after the fan and before the window I will have a 6" to 4" PVC reducer to fit over a standard laundry vent in the glass block window. The fan is rated for 449 CFM so at this point with the one 90 degree elbow and reducer, we shouldn't be dealing with a whole lot of slow down in air flow.

The exterior options is where it gets tricky. In order to allow more airflow in through the window I have decided to add a rectangular vent window in the middle of the glass block, which leads me to the issue of recirculating the exhaust air back in the window when opened for make up air. My window will be set up just like this:



As you can see in the images to the right, my first idea is to have the 4" pvc coming out the window and then add another 90 degree elbow on the end of the tube after it exits the window driected to the right. This would help direct the exhaust gasses to the right and hopefully far enough away to keep most of the hot, humid air from getting sucked back in. The addition of one more elbow will add some more static pressure and slow down the airflow, but I hoping not much.

The second option, number two on the right, has a 90 degree elbow on the end of the 4" PVC pipe coming through the window pointed upwards. I would add another foot or so of 4" PVC pipe pointed upward, and then one more 90 degree elbow on the end of that pipe pointing to the right. The extra elbow on the top of the tube is added to prevent any rain from getting in the pipe, with the extra tube length to get the exhaust air further away from the make up air untake in the middle of the window. I was hoping that this set up would take advantage of the fact that hot air rises and by venting above the window it would decrease the risk of re-circulating the same air back in the room. The kicker here is that it adds another foot or so of 4" PVC pipe which is more constrictive then the 6" PVC pipe as well as another elbow. What I might gain in a less likely set up for re-circulating the exhaust air may result in even more of a drop in ariflow.

Anyway, long story short, what do you guys think of my options? I would like to try both and measure the drop in airflow from adding the extra pipe, does anyone know how to measure the CFM flow in duct work? Thanks guys!

How about cutting a hole in the block wall instead of tearing apart that nice glass block window? Or easier yet (IMHO) cutting the exhaust hole through the rim board of the floor framing? It's probably a 2x10 and taking a 4" hole out of the middle of the floor joists will not harm anything.

I don't have any of the tools to bore a 4" diameter hole in my foundation wall so I am not sure that solution would be much easier for me than having the glass block window re-configured. Going up through the floor joists could be a possibility, though I still would have to get through the exterior brick with a drill bit somehow.

I got a quote for a new window with the proper vents installed for $150 bucks so I am really leaning towards that option right now I think. Thanks for the ideas, I may investigate going through the joists and exterior brick option a bit more as that sounds more doable with the tools I have on hand...

NattyBrew said:

I don't have any of the tools to bore a 4" diameter hole in my foundation wall so I am not sure that solution would be much easier for me than having the glass block window re-configured. Going up through the floor joists could be a possibility, though I still would have to get through the exterior brick with a drill bit somehow.

I got a quote for a new window with the proper vents installed for $150 bucks so I am really leaning towards that option right now I think. Thanks for the ideas, I may investigate going through the joists and exterior brick option a bit more as that sounds more doable with the tools I have on hand...

Click to expand...

Cool. Hope everything works out perfectly for you.

Thanks for the suggestions, gotta keep the mind churning to come up with an ideal solution here.

I know it isn't the same as measuring true CFM, but couldn't I jut use an anemometer to measure wind speed at the end of the exhaust pipe in different configurations and compare? I know there has got to be something I would be missing in the physics of CFM. Any HVAC techs on this site? Haha

Another option to consider on your outlet vent through the window is to extended it out further from the window so the distance between the outlet and the inlet are further apart.

I think I get what you are saying, just extend the pipe straight out from the side of the house further to get the vent air further from my inlet window. I didn't even think of that. There really isn't anything on that side of the house so a pipe sticking a little further out from the wall wouldn't be too bad. As long as it doesn't end up being more than a foot or two.

I think my plan is to get all the interior pieces assembled since the plans there for the most part aren't changing then just by a bunch of elbows and short pieces of PVC pipe and try them all out. I think the key is to make sure all this nonsense on the outside of the house doesn't restrict the CFM and airflow of the fan too much to properly vent the steam from my brew room.

Thanks as always for the ideas guys!

Yes, that is what I meant

If you can do that, it would be less restricting than the additional elbow you were showing in option 2.

RE: going through the wall for a 4" hole

Find a tool rental supply place, and rent a 4" core drill. They can be rented by the hour and run anywhere from $40-80 around here depending on the type you rent. You can do it yourself and place it where you relatively inexpensively.

Just another option to consider.

I work in the trades and and I am sure that it is difference in nomenclature but you really don't want to cut a 4" hole in your floor joists I am sure you meant that cutting a 4" hole in the rim joist the one on the outside perimeter of your house is fine

The standard way of running a vent is to use insulated duct work so you don't get condensation

The core drill is the way to go but you can also grind out the mortar and take out some bricks and chip away at them with a cold chisel and reinstall them leaving you a 4" hole

Dave

Burrning Barn Brewing

Is the vent pipe high enough to keep critters out, or does it have a magic flap ? I worry about creatures if I don't get the pipe high enough since I brew in the basement (no vent pipe yet -- just using a window fan)