Building a cool room

In the planning stages of building a cool room in the basement.
My basement gets pretty warm (near 80) during parts of June then July and August and we want a place to keep both wines and beers at a more stable temperature all year.

Going to install a window AC in one wall and build the room using rough cut full 2X4’s so I can have extra insulation, walls will be skinned in OSB.

Room will be 9 X 6 feet and have one door.

Any feedback ideas would be appreciated

If the fuel tank is going to be in the conditioned room it may effect your wine, just a thought.

You would have better luck putting the AC on an outside wall if your basement gets that warm in the summer too because the condenser coil side will heat your basement even more, possibly to the point it will burn the compressor out, they’re generally only designed to operate in temperatures below 105 degree ambient temperatures.  The warmer the ambient air the harder the compressor has to work to raise the condensing pressure in order to reject heat.  The condenser will steadily raise the basement temperature forcing the compression ratio to climb also.  You could duct outside air into the condenser, or maybe get some outside air cross ventilation going though and it may keep the basement temperature down low enough.  A lot of it will depend on how much product you load it with and temperature of the product.  Sealing the cold room up well will help a lot too.

Because the AC becomes a fixed appliance, you may have to install a dedicated circuit for it which requires a permit. I have been looking into getting a permit for the wiring I want to do and the thing about the installed appliance was in one of the books I read about wiring.

Kai

The casement windows stay open in the Summer so that will help with the warm air created by the AC
I’ll probably provide an insulated duct to help vent the warm air out through a window though.

Oil tank is sealed up tight and vented outside.
I’ve never had a sniff of fuel oil in the basement even after a fill up but will definitely keep that in mind as the project nears completion

Use at least a couple of inches of foam board insulation on the inside and seal the joints well. You can add fiberglass insulation behind that if you want, but don’t put fiberglass insulation directly in contact with the cool air space. Also, the the vapor barrier, which you’ll definitely need, goes on the outside, not the inside.

The oil tank is part of my fermentation room as well. Initially I thought of excluding it but that would have reduced the available space significantly. It doesn’t bother me that it is there.

Kai

Gonna use a Love controller for the room temp?

Probably a digital thermostat that I have laying around the house doing nothing.

Make sure the thermostat can handle the current that a stating AC generates. I know that our full house AC dims the lights a bit when it starts up.

Kai

What I’ll do is bypass the thermostat on the AC itself and set the AC on full cold and let the thermostat cycle it.

I use an ETC digital thermostat, but I sense the temperature of  the cooling coils to prevent icing. Once you get a little experience with your room, you can adjust the deadband and setpoint of the control and your desired room temperature will stay very constant.

Yes, that’s what I would do as well, but make sure the thermostat is rated for the load of the AC which should be inductive. Many switches have a lower load rating for inductive lods since they can cause arcs to form when they are switched off.

But others have build these rooms before, maybe it is not as much of an issue as I think.

Kai

Just use your thermostat as a master to control a slave relay. I use a Hunter room t-stat to control my chest freezer, but via a slave relay.

Let me know if you need any parts, or a diagram to do it. his is exactly how I controll my fermentation chamber.

Is there an exhaust duct for the warm air from the A/C?

Nice setup. I’d like to have a climate controlled room someday. My basement runs about 58-60 degrees in the winter and peaks at 70-72 in the dead of summer. It would be nice to be able to smooth that out to 60ish all year round.

Nope. No exhaust. Being as it is in he basement to begin with, it is already cool down there, so it really does not throw off a lot of heat. Even if it did, it would not matter to me, since i’m only down there on brew day.

You need a catwalk.

ROFL
Nice!