kickrjason
Well-Known Member
Who out there has built a fermentation chamber based on a window A/C unit? I would like to know what has worked and what has not worked?
Fermentation Chamber A/C Unit
- Thread starter kickrjason
- Start date
Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:
Check out the threads at the bottom of this page, or just do a search for fermentation chambers, or browse through the DIY section. I've seen a lot of threads of ferm chambers with ac's.. they work.
OP
OP
kickrjason
Well-Known Member
Ok apparently i need to be more specific in my questions to avoid responses like that........ Fyi i know how to search the forum.
I would like to know from the people that have built them that use them on a constant basis.
1) what have you run into as far as condensation problems.
2) have you wired in a digital controller for more precise temperature management.
3) what kind of power consumption do you insure from running the unit
Thank you
I would like to know from the people that have built them that use them on a constant basis.
1) what have you run into as far as condensation problems.
2) have you wired in a digital controller for more precise temperature management.
3) what kind of power consumption do you insure from running the unit
Thank you
I do not have one but i do remember reading about some builds. IIRC most of them had to add some small computer fans or similar to the condenser coils to keep it from freezing up. That seemed to be a reoccurring problem.
ilikethetrees
Well-Known Member
I've built a fermentation chamber that uses a window AC unit. See here: https://www.homebrewtalk.com/f51/my-fermentation-chamber-build-question-262827/
It works great. I got the Johnson A419 controller. No condensation problems.
Here are a few things I learned in the process, in no particular order:
AC units have a built-in thermostat that will probably turn the coolant compressor off at 60-ish degrees F. You'll need to bypass that. In my case, I was lucky because the AC unit isn't digital. Bypassing the AC unit's built-in thermostat was really easy with a little wiring logic.
Make sure you attach your external thermostat's probe to something with thermal mass. I have mine wrapped in plastic and floating in a little gallon jug of water so the Johnson controller only kicks on the AC unit when the liquids in my chamber are above a certain temperature. This is important because air loses energy way faster than a 5 gallon batch of beer. If you don't do this your AC unit will cycle many times an hour and burn the compressor out.
I don't have condensation issues because my AC unit only cycles once an hour or so. Don't skimp on insulation sheets, Great Stuff, caulking, or the seal around your door. The seal around your door is crazy important to seal well. I made mine big enough to actually sit in, and I did just that to see where the leaks were. Wherever I saw light, I improved the seal around the door until it was tight. If I were to build this over again, I would plan my door construction way better. Hell, I could fix it now, but I'm lazy. Works great.
If you're using an AC unit, you can get things really cold, as long as you can bypass the AC unit's thermostat, so take advantage of that and make the thing as big as you can afford to. When sizing the external dimensions, consider making the thing portable and narrow enough to fit through doorways/stairwells. Instead of crappy pine 2x4s for the framing I bought some decent maple. Glad I did, it took way less wood to build the skeleton and as a result I can move it very easily.
Great Stuff is insanely sticky and will completely F up your skin! SWMBO was not happy about my cancer hands.
Insulation sheets are cheaper than ruined batches of beer, so go nuts, treat yourself to the 2" thick high R factor stuff.
Consider the future. I might start fermenting in kegs one day, so I made sure I could fit a keg with a fermentation rig fitted to it inside in terms of height. (I didn't plan space for conicals, but that's another story altogether.)
The Johnson controller is nice, but you might as well go for something with two channels on it, one for heating, one for cooling. Even if you live somewhere that doesn't get too cold in the winter, you might want the heating option later for a saison or something Belgian that wants a higher temp.
Can't stress this enough: GO BIG!!! I feel a little sad when I see fermentation chambers that can only fit 2 carboys. An AC unit puts out a ton of cooling power, even a little 5000 BTU unit. Make the most of it! I spent a couple hours ripping apart a minifridge to get the guts out, but for my money, the AC unit is way more powerful and efficient.
Power consumption is probably a few bucks a month. What's it worth to you to have awesome beer year round? This is probably the best investment you could make in beer quality, aside from oxygenation. FEED YO YEAST, SON!
Hopefully that answers some of your build questions! Holler if you have more.
TJTHEBEST
Well-Known Member
I've built a fermentation chamber that uses a window AC unit. See here: https://www.homebrewtalk.com/f51/my-fermentation-chamber-build-question-262827/
It works great. I got the Johnson A419 controller. No condensation problems.
Here are a few things I learned in the process, in no particular order:
AC units have a built-in thermostat that will probably turn the coolant compressor off at 60-ish degrees F. You'll need to bypass that. In my case, I was lucky because the AC unit isn't digital. Bypassing the AC unit's built-in thermostat was really easy with a little wiring logic.
Make sure you attach your external thermostat's probe to something with thermal mass. I have mine wrapped in plastic and floating in a little gallon jug of water so the Johnson controller only kicks on the AC unit when the liquids in my chamber are above a certain temperature. This is important because air loses energy way faster than a 5 gallon batch of beer. If you don't do this your AC unit will cycle many times an hour and burn the compressor out.
I don't have condensation issues because my AC unit only cycles once an hour or so. Don't skimp on insulation sheets, Great Stuff, caulking, or the seal around your door. The seal around your door is crazy important to seal well. I made mine big enough to actually sit in, and I did just that to see where the leaks were. Wherever I saw light, I improved the seal around the door until it was tight. If I were to build this over again, I would plan my door construction way better. Hell, I could fix it now, but I'm lazy. Works great.
If you're using an AC unit, you can get things really cold, as long as you can bypass the AC unit's thermostat, so take advantage of that and make the thing as big as you can afford to. When sizing the external dimensions, consider making the thing portable and narrow enough to fit through doorways/stairwells. Instead of crappy pine 2x4s for the framing I bought some decent maple. Glad I did, it took way less wood to build the skeleton and as a result I can move it very easily.
Great Stuff is insanely sticky and will completely F up your skin! SWMBO was not happy about my cancer hands.
Insulation sheets are cheaper than ruined batches of beer, so go nuts, treat yourself to the 2" thick high R factor stuff.
Consider the future. I might start fermenting in kegs one day, so I made sure I could fit a keg with a fermentation rig fitted to it inside in terms of height. (I didn't plan space for conicals, but that's another story altogether.)
The Johnson controller is nice, but you might as well go for something with two channels on it, one for heating, one for cooling. Even if you live somewhere that doesn't get too cold in the winter, you might want the heating option later for a saison or something Belgian that wants a higher temp.
Can't stress this enough: GO BIG!!! I feel a little sad when I see fermentation chambers that can only fit 2 carboys. An AC unit puts out a ton of cooling power, even a little 5000 BTU unit. Make the most of it! I spent a couple hours ripping apart a minifridge to get the guts out, but for my money, the AC unit is way more powerful and efficient.
Power consumption is probably a few bucks a month. What's it worth to you to have awesome beer year round? This is probably the best investment you could make in beer quality, aside from oxygenation. FEED YO YEAST, SON!
Hopefully that answers some of your build questions! Holler if you have more.
That was a great summary! Im thinking ill go this route someday
ilikethetrees said:I've built a fermentation chamber that uses a window AC unit. See here: https://www.homebrewtalk.com/f51/my-fermentation-chamber-build-question-262827/
It works great. I got the Johnson A419 controller. No condensation problems.
Here are a few things I learned in the process, in no particular order:
• AC units have a built-in thermostat that will probably turn the coolant compressor off at 60-ish degrees F. You'll need to bypass that. In my case, I was lucky because the AC unit isn't digital. Bypassing the AC unit's built-in thermostat was really easy with a little wiring logic.
• Make sure you attach your external thermostat's probe to something with thermal mass. I have mine wrapped in plastic and floating in a little gallon jug of water so the Johnson controller only kicks on the AC unit when the liquids in my chamber are above a certain temperature. This is important because air loses energy way faster than a 5 gallon batch of beer. If you don't do this your AC unit will cycle many times an hour and burn the compressor out.
• I don't have condensation issues because my AC unit only cycles once an hour or so. Don't skimp on insulation sheets, Great Stuff, caulking, or the seal around your door. The seal around your door is crazy important to seal well. I made mine big enough to actually sit in, and I did just that to see where the leaks were. Wherever I saw light, I improved the seal around the door until it was tight. If I were to build this over again, I would plan my door construction way better. Hell, I could fix it now, but I'm lazy. Works great.
• If you're using an AC unit, you can get things really cold, as long as you can bypass the AC unit's thermostat, so take advantage of that and make the thing as big as you can afford to. When sizing the external dimensions, consider making the thing portable and narrow enough to fit through doorways/stairwells. Instead of crappy pine 2x4s for the framing I bought some decent maple. Glad I did, it took way less wood to build the skeleton and as a result I can move it very easily.
• Great Stuff is insanely sticky and will completely F up your skin! SWMBO was not happy about my cancer hands.
• Insulation sheets are cheaper than ruined batches of beer, so go nuts, treat yourself to the 2" thick high R factor stuff.
• Consider the future. I might start fermenting in kegs one day, so I made sure I could fit a keg with a fermentation rig fitted to it inside in terms of height. (I didn't plan space for conicals, but that's another story altogether.)
• The Johnson controller is nice, but you might as well go for something with two channels on it, one for heating, one for cooling. Even if you live somewhere that doesn't get too cold in the winter, you might want the heating option later for a saison or something Belgian that wants a higher temp.
• Can't stress this enough: GO BIG!!! I feel a little sad when I see fermentation chambers that can only fit 2 carboys. An AC unit puts out a ton of cooling power, even a little 5000 BTU unit. Make the most of it! I spent a couple hours ripping apart a minifridge to get the guts out, but for my money, the AC unit is way more powerful and efficient.
• Power consumption is probably a few bucks a month. What's it worth to you to have awesome beer year round? This is probably the best investment you could make in beer quality, aside from oxygenation. FEED YO YEAST, SON!
Hopefully that answers some of your build questions! Holler if you have more.
I agree on getting a dual stage controller;i like being able to heat or cool.
I don't really agree that bigger is better. I wanted a small chamber, not a walk in cooler. I've never wanted more than 2carboys at once. The fact that the ac is oversized doesn't bother me.
OP
OP
kickrjason
Well-Known Member
It answered a lot of my questions. Thank you for such a thorough reply.
I have an Stc-1000 that it wired up to a mini fridge right now. Would I wire the controller up the same way to power the A/C unit or should it be relayed? Can the controller handle the power that the unit will pull? you said you had to wire up the built In Thermostat. Did you bypass it or remove it entirely and just set it to run when plugged in?
I think I got a junk fridge and now am looking for a better replacement.
On a plus if and when I switch to an A/C unit I will gain more space.
Sent from my iPhone using HB Talk
I have an Stc-1000 that it wired up to a mini fridge right now. Would I wire the controller up the same way to power the A/C unit or should it be relayed? Can the controller handle the power that the unit will pull? you said you had to wire up the built In Thermostat. Did you bypass it or remove it entirely and just set it to run when plugged in?
I think I got a junk fridge and now am looking for a better replacement.
On a plus if and when I switch to an A/C unit I will gain more space.
Sent from my iPhone using HB Talk
dutchoven
Well-Known Member
kickrjason, do you have an AC unit already? If not, have you thought about using a freezer? Food for thought, I know you've already built your chamber ...
OP
OP
kickrjason
Well-Known Member
Yea i am committed to the chamber at this point. Lots of $$ in supplies and time. I can remove the fridge, Insulate the rest and put the A/C unit in the end relatively easily.
the SWMBO would probably question my abilities if i abandoned the cabinet i just spent a solid day building.
dutchoven
Well-Known Member
I feel ya ... good luck with the build.
ilikethetrees
Well-Known Member
I've never dealt with an STC-1000 before, but I wired my Johnson a419 to an extra power cable that plugs in to the power cable of the AC unit. It isn't directly wired to the AC unit. Is that what you mean?
My Johnson A419 handles the current draw fine. This should answer any questions you have about the Johnson A419 controllers in particular: http://cgproducts.johnsoncontrols.com/MET_PDF/125188.PDF
When I bypassed the built-in thermostat in the AC unit, it was a matter of eliminating the circuit that went to the temp probe. It was a literal bypass in that I skipped that part of the circuit, making the line coming from the power source go straight to the compressor and fan without running to the temp probe. As I understand it from other threads, every AC unit is different, and that operation might get a lot trickier if there's some type of printed electronic circuit board with those components on it. Look for AC units with knobs instead of buttons and LCD screens or lights.
I have read about folks either bending the temp probe so it sticks outside the chamber or (very cleverly!) wiring some sort of little light bulb or other item that will generate small amounts of heat to the temp probe, thus making the AC unit always think the inside of your chamber is hot.
Rewire these things carefully and at your own risk! Capacitors are not your friend.
ilikethetrees
Well-Known Member
Freezers will definitely save money! I ended up spending more on my chamber than it would cost to get a big ol' chest freezer. On the up side, I now have something with the perfect dimensions to ferment large amounts of beer, but everyone's space requirements vary. I happened to have an extra AC unit, so that wasn't part of the cost.
Similar threads
