I used to have a 3 way fridge when running on gas it would freeze.
So one of the bigger fridges for caravans might do the job very well if you have space for it.
Not as energy efficient but very compact a Peltier device could provide cooling. Its a trade off though size for energy, I doubt there is anything more compact. Some US homebrew company stuck one on the end of a heat pipe that ran into a FV.
Aamcle
Off-grid FV temperature control possibilities?
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Kev888
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Re: Off-grid FV temperature control possibilities?
Thats good to know, thanks - I was looking at a waeco 3-way cool box earlier, that wasn't said to be as cold on gas or 12v as on mains electricity, so its good to know the proper fridges are better.
Yeah, I followed Naich's peltier/TEC builds over on JBK and theres no doubt that their compactness would be a big benefit, and they could be used to heat too making things even more compact. I've been wrestling to find a way, but as you say, they aren't very efficient and would need a pretty good (and so expensive) source of power to work reliably off-grid. The 12v compressor fridges would be more efficient than peltiers, at the cost of size, but even then much of their low electricity demand is due to heavy insulation, which wouldn't be so applicable if they're busy fighting exothermic fermentation.
So I suspect it would probably be cheaper and more reliable to get a used 3-way/absorption fridge and just run it on a propane cylinder, which I'll have anyway for powering the boiling ring. If I simply took ice from it manually or had a small reservoir in there then it could still be used as a fridge, so I wouldn't be dedicating all that weight and bulk to just controlling the FV, which makes it a bit more viable. The main downside is that it would probably need much more effort to install and move about, due to venting the spent gas safely.
Cheers
kev
Yeah, I followed Naich's peltier/TEC builds over on JBK and theres no doubt that their compactness would be a big benefit, and they could be used to heat too making things even more compact. I've been wrestling to find a way, but as you say, they aren't very efficient and would need a pretty good (and so expensive) source of power to work reliably off-grid. The 12v compressor fridges would be more efficient than peltiers, at the cost of size, but even then much of their low electricity demand is due to heavy insulation, which wouldn't be so applicable if they're busy fighting exothermic fermentation.
So I suspect it would probably be cheaper and more reliable to get a used 3-way/absorption fridge and just run it on a propane cylinder, which I'll have anyway for powering the boiling ring. If I simply took ice from it manually or had a small reservoir in there then it could still be used as a fridge, so I wouldn't be dedicating all that weight and bulk to just controlling the FV, which makes it a bit more viable. The main downside is that it would probably need much more effort to install and move about, due to venting the spent gas safely.
Cheers
kev
Kev