Thermoelectric (peltier) glycol chiller for flooded font

Aussie Home Brewer

Help Support Aussie Home Brewer:

squirt in the turns

Well-Known Member
Joined
23/4/10
Messages
266
Reaction score
33
My chest freezer based keggerator set up made a big leap forward yesterday with the acquisition of 2 4-tap flooded fonts. I always thought of flooding as a nice-to-have feature to help prevent foaming issues when pouring that first beer of a session, and never thought about getting the whole ice thing going on. I mean, let's face it: it's a bit wanky.

But now I have the flooded fonts, I kind of want that icy goodness. My idea is to have a glycol reservoir in the freezer (at normal serving temp of about 4°C) with an aquarium pump to feed the fonts. Under normal operation, this should be sufficient to run for a few mins before the first pour to chill the fonts and lines down. Positioned in-line between the pump and the fonts will be a copper water block like those used to liquid-chill CPUs. The cold side of a peltier attaches to the water block while the hot side will have a nice big heat-sink and fan assembly. When ice on the font is required, the peltier gets turned on, further chilling the coolant on its way to the fonts. I'm thinking I'll mount it such that the heat-sink is through the keggerator collar, and so is cooled with ambient air. Having the heat-sink inside the freezer might result in a faster initial chill, but I think the net effect is most likely that the peltier's excess waste heat will warm up the kegs pretty quickly.

I know there are some equations out there for peltiers that I can (and probably will) use to figure out how well, if at all, this will work. At this stage I'm just throwing this idea out there to see if I'm way off track or if anyone's done something similar.

A couple more questions: what temperature should the glycol mix be run at to get ice on the font, but not freeze the beer in the lines?

With 8 taps I guess I'm going to need a pretty big drip tray. It's going to need to surround the bases of these fonts too, if they're going to be covered in condensation. Is custom fabrication my only option?
 

Online Brewing Supplies

**** OBS ****
Joined
17/5/06
Messages
4,739
Reaction score
639
Location
The Dean WA
Beer depending on alcohol content will freeze at 0 to -3
Peltiers are inefficient and will only go a set amount below ambient temps. I have thought about it before but decided against it.
Nev
 

donburke

Well-Known Member
Joined
18/1/09
Messages
1,395
Reaction score
107
My glycol chiller sits at between -1 and -2 in winter and -2 and -3 in summer in order to maintain a nice layer of ice on the font without freezing the beer in the lines
 

squirt in the turns

Well-Known Member
Joined
23/4/10
Messages
266
Reaction score
33
Thanks for your responses guys. I might do some rough calculations to determine if it has any hope of working, although most of the info out there is geared toward calculating temperature reductions for CPUs with a known heat load. Not really sure how I'd work out the heat load of the coolant passing through the water block.

I only need to drop the coolant temperature by 5 or 6°, but I'm looking at a temperature difference from the hot to the cold side of the TEC of maybe 27 degrees, assuming the heatsink is outside the keggerator. I'll probably just try it as a peltier and a water block will probably set me back less than $50.
 

Latest posts

Top