Glycol Chiller Home made.

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Anyone here managed to make their own GC chiller from old air-conditioning unit?
Seems common over the pond with old window mounted AC units but dont think we have them here so has anyone managed it??
 
I have seen someone that did it over here, and I nearly had a go myself - I got one of the portable a/c units on wheels (pretty cheap second hand on the usual online places) and stripped it down: they have a separate condenser and chiller part to them (one above the other) but plumbed in rigid tube. Apparently if you’re careful you can bend the tubing enough to immerse the chiller side in a glycol bath, and then pump the chilled glycol around the jacket of your FV or whatever.
I got as far as rejigging the temperature control sensor to get the unit to go down to near-freezing temps, and being able to control it via the built-in IR board; but the glycol bath just looked like a lot of hassle so in fact I ended up converting a couple of fridges into kegerators/fermentation chambers. That was a better shout I think, because otherwise making a suitably well-insulated enclosure is quite a pain.
 
I have two freezers in my garage next to where I ferment that run at about -20. I have to admit the thought was not lost on me. It's just getting those two hoses and power cable out stops me.......... for now
 
Alot cheaper to repurpose a maxi chiller. Currently re-configuring mine. Going to use the continuous flow and an old home made copper immersion chiller in a coolbox of glycol:-

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Will need to put a non return valve or check valve on the output of the pump to prevent the glycol emptying into the cool box when the pump is off. Got the maxi chiller for about £200 off eBay, small cool box for £20 off FB market place.

Had it set up differently previously without the toolbox and running a closed line of glycol through the chiller product coils. Worked fine but struggled to cold crash to below about 3 or 4 degree's. Hoping the continuous flow through the copper coil will get the glycol bath a bit colder. If its good enough to cover a bar pump in ice then it should be cold enough to get the glycol nice and cold.

A mate of mine has a chiller and a bucket of glycol and just runs the glycol through the product coils and again struggles to cold crash to a decent temperature. Keep telling him to get a small larder freezer and put the bucket in the freezer.

Saw a YouTube video of a microbrewery in the states where the chap was using a small chest freezer, completely filling it with glycol and running a few fermenters off that.
 
I believe the water gets below zero. Though it ices up around the edge of the bath inside the chiller that the product coils run through the bulk of it is kept from freezing as its continually pumped around a circuit and it's this that is circulated through the bar pumps that have ice forming on them, so I assume its below freezing. in my previous set up where I was circulating the glycol through the product coils I struggled to get the glycol much above a couple of degrees as its only going through Ice, however if I can ge the glycol in the coolbox to zero or a degree or two below then that should be fine. I'm only running one fermenter from it.

If it's not cold enough then I can bypass the chiller thermostat and run a separate temp controller and replace the water with glycol and cool to about -5. There are a few people who have made this mod and running their chiller like this.
 
Last summer I used a water tank in the keezer to hold 20l of water for cooling. This was ok, all connections made through the collar. Main issue being the temperature discrepancy, you can’t just super chill the kegged beer to get better cooling water.

This year the keezer is full for its actual purpose so that isn’t an option. I’m more or less decided that I will get a 30-50l fridge or freezer and stand the fermenter on it.
 
Will need to put a non return valve or check valve on the output of the pump to prevent the glycol emptying into the cool box when the pump is off. Got the maxi chiller for about £200 off eBay, small cool box for £20 off FB market place.

Be careful with that.

You can easily set a thermal syphon going, which is confusing until you twig-on.

I leave the return hose above the coolant level, so that it drain& most fluid being chilled.

Also consider fermentation temperature maintenance and cold crashing are potentially two completely different requirements.
 
I have two freezers in my garage next to where I ferment that run at about -20. I have to admit the thought was not lost on me. It's just getting those two hoses and power cable out stops me.......... for now

Brilliant solution I was really pleased with it.

Solved the scarey hole issue.. Patience & a bit of detective work is required.
A white plastic bath drain, is perfect and easy to seal up when not it use.

Inline Kettle plugs on the pump lead will pass through the hole.

One pair AC250V 10A IEC C14 Male C13 Female, 3 Pins Terminals Inline Adapter Plug Power Socket Connectors https://amzn.eu/d/0fXaELy

Mahoosively cheaper than a maxi. And all the bits can be used for other jobs.
 
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Yeah the hot bit is at the back externally but the coolant runs through fins under every shelf. Just wondering if it does this then does that mean the sides could be clear of plumbing. Don't want to be the one that hears the hiss of doom as the drill goes through the gas pipes.
 
Nope. Evaporation coils in the sides.

If your mobile has thermal image that's handy. You can also use a ir gun.

There are also some info on the net, depending on the brand.
 
Be careful with that.

You can easily set a thermal syphon going, which is confusing until you twig-on.

I leave the return hose above the coolant level, so that it drain& most fluid being chilled.

Also consider fermentation temperature maintenance and cold crashing are potentially two completely different requirements.
This is what I'm trying to suss out. Not sure if normally the jacket is emptied between cooling cycles. In my current configuration its not and don't have any trouble maintaining fermentation control, the temperature adjustment is not that great - just half a degree or so adjustment at a time, and cold crashing works fine too apart from not being able to get below about 3 degrees, it will cool 60 litres from fermentation temperature to 3 degrees in an hour or so.

I've deliberately used as small a coolbox as I can, just large enogh to accommodate my immersion chiller. The thinking here is that with a smaller volume of glycol the cooling coil will chill it down more quickly. So if I do get any siphoning then I don't have the volume to accommodate the entire glycol volume, hence the check valve.

Not sure if I should have the return line terminating above the glycol level or below it. If I do get syphon from the top, then that'll just draw up glycol from the coolbox...and I would have inadvertently have invented a perpetual motion machine!
 

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