Window AC Water Bath

[fearwig]

I'm not unhandy, but HVAC is not my forte (yet?). I've seen window units used to chill glycol baths. Would it be possible to set up a unit with its condenser coils dipped in a water bath in the same way, say, with a water pump to agitate, or would that freeze up right away, or, I don't know, fray the space-time continuum or kill me somehow?

It seems to me like the density of the water should prevent the sort of freezing you get from high-humidity air, so that doesn't seem like an issue. Corrosion, maybe?

I already brew in water baths almost exclusively, because I frequently want to get up above ambient in my basement (at least during the winter) and aquarium heaters are cheap and easy, but if I could lager with a similar sort of setup and minimize the need for an airtight system, that seems pretty ideal to me.

 

[bemerritt]

Are you saying you want to have a fermenter (bucket or carboy) in a water bath and then control the water bath temp with an ac unit to keep temps within an acceptable range? If so, yes. It will work. Like you said, you will need a pump that is continuously on.

Wire up an stc with the ac on the cooling relay and the aquarium heater on the heating relay. Ideally, you want the temp probe monitoring the temp inside the beer, but if you don't feel like rigging up a way to hang the temp probe in the fermenter while keeping it airtight, monitoring the water bath should be close enough.

This is a very similar setup to that used with my jacketed conical, except I pump the water through it and I use a bcs to control it. If you are going through all of this trouble, i would continue the fun and try and jacket whatever you are fermenting in. Wrap some copper tubing around it, insulate it and then pump your temp controlled water glycol through it.

One last note. Adding glycol allows you maintain lower temps in the bath. I read somewhere that you don't want the bath to get around 40 *F due to coils freezing unless you add some glycol in the mix. However, glycol does not conduct heat as well as water and food grade glycol can run about 30 bucks per gallon.

Hope this helps!

 

[fearwig]

Sure does! I'm pretty psyched, now I just may work out a bigger bath than these 2-bucket rubbermaids... Kiddie pool is sounding good, haha.

 

[bemerritt]

Try a big cooler. The insulation will help keep temps stable. Here is a pic of my setup to help with your creative juices.

edit:

this pic shows the ac part better

 

[fearwig]

I doubt think they make a cooler big enough, I'd like to fit at least two five-gallon HDPE buckets (preferably two 6.5s), plus the AC. I'll be sure to report back with pics if and when.