Dual stage walk-in

[shtank]

Hey folks,

I want to build a walk in about 6' tall 3' wide and 6' deep with a door on the inside separating the two sides. One side will be for serving and will have taps out the wall the other for my half barrel chronical that I will just roll inside.

The question is do you think I can do this with just 1 ac unit on the serving side with a fan blowing cold air to the fermentation side. I will probably do 2 temp controllers with only one of them being duel stage controlling the fan and a small heater.

Thanks in advance
Cheers

 

[porterpounder]

I think it depends on how large an area the fan takes up in the partition. If it's a big box fan then that AC will be working overtime to keep the cool side cool. If it's a more powerful small diameter fan then it may be OK. I'd also worry about even having a room for a door between the two sides. How will it open with stuff in the way? I'd put a solid partition with the fan in it and make a door to each side to allow access from the outside.

 

[Onkel_Udo]

Whatever method you use, keep in mind that you have to have air circulating back into the cold(er) side from the warm(er) side. Two smaller fans, one blowing into the fermentation chamber and one blowing sir back into the serving area are probably best and spacing them as far apart as possible is the most efficient way to circulate.

 

[shtank]

I think it depends on how large an area the fan takes up in the partition. If it's a big box fan then that AC will be working overtime to keep the cool side cool. If it's a more powerful small diameter fan then it may be OK. I'd also worry about even having a room for a door between the two sides. How will it open with stuff in the way? I'd put a solid partition with the fan in it and make a door to each side to allow access from the outside.

I was going to do a door for a partition. Only because my conical will be on wheels and I could just roll it out of the way. Plus less doors equals less leaks.

I was thinking a small fan near the floor.

 

[shtank]

Whatever method you use, keep in mind that you have to have air circulating back into the cold(er) side from the warm(er) side. Two smaller fans, one blowing into the fermentation chamber and one blowing sir back into the serving area are probably best and spacing them as far apart as possible is the most efficient way to circulate.

This is exactly why I posted. These are the things I would never think of. With that being said why would I need to bring air back to the cold side?

 

[Onkel_Udo]

This is exactly why I posted. These are the things I would never think of. With that being said why would I need to bring air back to the cold side?

In short, where is the air coming from that you are pumping out of the cold side...what replaces it. Where does all the extra air the warm side is receiving from the cold side going to go?

Assume you have forced air heating or cooling in your house, this works the same way. Air has to enter the air handler to be blown out through the ducts. For obvious reasons, it is not a good idea for all that air to come from outside so you recycle the air with (at least one) return air duct(s).

 

[shtank]

I will have a fan running constantly on the cold side just to stir the cold air. Do you think it would be better to have the fan that's in the partition near the top? So the cold air can fall over the fermenter.

And would just a vent work for a return? If so up top or on the bottom?

 

[Onkel_Udo]

I will have a fan running constantly on the cold side just to stir the cold air. Do you think it would be better to have the fan that's in the partition near the top? So the cold air can fall over the fermenter.

And would just a vent work for a return? If so up top or on the bottom?

A return vent will work fine but as I mentioned, the best way to ensure the maximum circulation is two widely separated fans (upper left, lower right) pushing in opposite directions.

If you suck air out of the top of the serving room it will be the warmest air in the serving room BUT this is like the difference between 40 and 42f so no big deal.

 

[NoahBeach]

This is exactly why I posted. These are the things I would never think of. With that being said why would I need to bring air back to the cold side?

For recirculation. Your cold room(s) are going to be insulated and then sealed up as much as possible to keep the cold in. If you just had one fan blowing air from one side to the other, even with a leaky (inefficient) room your fan would be working against positive pressure to move air as it's going to try to push air faster than it can escape.

With two fans you're recirculating air, that way its being chilled warmed and then rechilled, much more efficient as a closed system.

 

[shtank]

OK. So I will put a fan coming out of the cold side on the top then a return fan at the bottom in hopes to give the cold side the coldest air.

Now what better fiberglass insulation or 2 layers of foam with plywood on the outside and some of the vinyl panel board on the inside?

 

[Onkel_Udo]

Now what better fiberglass insulation or 2 layers of foam with plywood on the outside and some of the vinyl panel board on the inside?

My opinion?

Studs
fiberglass in between the studs
thin (1/2-3/4") foam over the entire interior OVER the studs
Tape all foam seams
Interior wall covering of your choice over top but textured FRP (might be what you are referring to) is nice stuff...just pricey
Cover the exterior with whatever is appropriate to the area...if it is as a basement, use water resistant drywall and hold it at least a 1/2" off the floor

 

[NoahBeach]

My opinion?

Studs
fiberglass in between the studs
thin (1/2-3/4") foam over the entire interior OVER the studs
Tape all foam seams
Interior wall covering of your choice over top but textured FRP (might be what you are referring to) is nice stuff...just pricey
Cover the exterior with whatever is appropriate to the area...if it is as a basement, use water resistant drywall and hold it at least a 1/2" off the floor

Agreed fiberglass insulation and then foam. As thick fiberglass as you can fit in between your studs without compressing it. And then foam on the inside to up the R value even more, make up some for lost R value from studs, and have a smooth surface to mount your interior surface too.

The more insulation the lower the temp you can achieve AND the cheaper it is to operate. Also don't forget you need to insulate the wall between the chambers as well. Otherwise condensation with be your enemy.

 

[shtank]

Awesome, thank you for the good advice. Maybe I will take a few pictures when I'm done.

 

[shtank]

Awesome, thank you for the good advice. Maybe I will take a few pictures when I'm done.