In theory these only go down to 16ºC... however with a bit of ingenuity it should be possible to 'fake' the thermostat (NB: don't try this unless you know what you are doing)
Towards FV temp control...
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Many thanks for this, @Neil54 - funnily enough I've just been chatting online with my friend's brother-in-law who is an AC expert, and he too was mentioning the possibility of the evaporator freezing up, so it's something I need to be aware of.
The unit itself (as built) seems to have three 'modes': cooling, heating and dehumidifying ...
Well.. I'm delighted to say that despite being 10-15yrs hors de combat... the fans run, the compressor fires up, the condenser gets warm and the evaporator gets cold. Result!
Next step: manufacture an enclosure with thin ply and insulation board
Next step: manufacture an enclosure with thin ply and insulation board
Decided after much thought to build an insulated cabinet with air circulating via the A/C unit via a couple of flexible ducts.
That will at least let me manage my fermentation temps - the A/C unit goes from 25ºC to 16ºC (heating and cooling).
Lower temps should certainly be achievable but that's for Phase II.
Meanwhile, a pile of stuff arrived from Wickes on Friday so I've been beavering away in the garage building the cabinet.
Since these photos I've been cutting up the insulation (50mm expanded polystyrene) and fitting it into the carcass. I found that the electric carving knife does a pretty good job of making a clean cut (don't tell my wife!!)
That will at least let me manage my fermentation temps - the A/C unit goes from 25ºC to 16ºC (heating and cooling).
Lower temps should certainly be achievable but that's for Phase II.
Meanwhile, a pile of stuff arrived from Wickes on Friday so I've been beavering away in the garage building the cabinet.
Since these photos I've been cutting up the insulation (50mm expanded polystyrene) and fitting it into the carcass. I found that the electric carving knife does a pretty good job of making a clean cut (don't tell my wife!!)
![BREWING THERMOMETER STICKERS ACCURATELY MONITOR FERMENTING BEER & WINE LIQUID TEMPERATURES 5PCS HOME BREW SPIRITS WINE LCD ADHESIVE [US]](https://m.media-amazon.com/images/I/311DDjo2X3L._SL500_.jpg)
Just curious. If you are making a chamber to pump cool air con air around, why haven't you bought a fridge for the purpose?
I'm all for making and hacking stuff, but have I missed something on earlier posts that has made you select to create your own?
Cheers
It’s a very reasonable question - and I’m sure there’s a very reasonable answer, which I shall inform you of once it’s occurred to me...
I could concoct plausible sounding reasons like I wanted to customise the space so I had room for an FV and four cornies next to it, or I wanted to make use of the old AC unit... but I think the truth is that I just like making stuff (plus I don’t think my wife would be very keen on me dragging home a second hand fridge...)
UPDATE
Having finished the insulated cabinet, I used it for the fermentation of my last brew and it worked very well.
But I only used the heating side of my temperature control, and I'd still like to be able to cool faster than I'll easily be able to achieve with the A/C unit blowing cold air round the FV.
Therefore I'm re-examining DarrenSL's suggestion here:
I originally ruled this out as being far too complex, having had a quick look at the construction of industrial glycol chillers and how they work.
However a bit of googling reveals that 'homebrew' glycol chillers actually use a different approach: basically cannibalising an old A/C unit like mine, but just using the glycol as a medium for heat transfer rather than as part of the refrigeration cycle itself. Now THAT is achievable, and it's something I'm actively exploring. For example see this link.
I still think the air-coupled system would work fine, in effect it's a bit like a commercial blast chiller, and requires less drastic modifications to the A/C unit... but using glycol pumped through a coil immersed in the FV would be a nice way to do it.
Stay tuned...
Having finished the insulated cabinet, I used it for the fermentation of my last brew and it worked very well.
But I only used the heating side of my temperature control, and I'd still like to be able to cool faster than I'll easily be able to achieve with the A/C unit blowing cold air round the FV.
Therefore I'm re-examining DarrenSL's suggestion here:
I originally ruled this out as being far too complex, having had a quick look at the construction of industrial glycol chillers and how they work.
However a bit of googling reveals that 'homebrew' glycol chillers actually use a different approach: basically cannibalising an old A/C unit like mine, but just using the glycol as a medium for heat transfer rather than as part of the refrigeration cycle itself. Now THAT is achievable, and it's something I'm actively exploring. For example see this link.
I still think the air-coupled system would work fine, in effect it's a bit like a commercial blast chiller, and requires less drastic modifications to the A/C unit... but using glycol pumped through a coil immersed in the FV would be a nice way to do it.
Stay tuned...
Okay so it took a bit longer than expected due to other commitments, but I've finally hooked that old air conditioning unit up to the insulated cabinet I constructed for cold conditioning.
The AC unit works like a charm - I had to disable its room temperature sensor, because that only went down to 16ºC, and I'm now controlling it by sending it IR remote control control signals from an external controller box.
The only tricky bit mechanically was fitting the ductwork to circulate the airflow through the cabinet, which required a bit of ingenuity:
Anyhow, when fired up the unit seems to be extremely effective at cooling down the cabinet. Here it is in action chilling the cabinet temperature (red line) down to 5ºC:
The AC unit works like a charm - I had to disable its room temperature sensor, because that only went down to 16ºC, and I'm now controlling it by sending it IR remote control control signals from an external controller box.
The only tricky bit mechanically was fitting the ductwork to circulate the airflow through the cabinet, which required a bit of ingenuity:
Anyhow, when fired up the unit seems to be extremely effective at cooling down the cabinet. Here it is in action chilling the cabinet temperature (red line) down to 5ºC:
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