I've had a chiller for a few years -I posted when I first got it from a mate (sorry pics lost when I changed ISP).
Anyhoo I had another good look inside it again at the weekend to see how to go about controlling the output temperature. There are two thermostats with dials on the front, 1 controlling 2 lines, another controlling 1 (but just the one water bath & circulator??) and what looks like another one inside. The problem is they both terminate inside the casing of the water bath which is well sealed and I didn't fancy getting forceful and borking it.
One solution I've come up with is bypassing the existing thermostats and measuring the temperature of the water bath and the output from the product coils. Once I've got a linear relationship I can apply an offset and control the recirc pump from a microcontoller (ESP8266).
Thoughts ladies and gents?
Cheers
Jamie
Inline chiller (maxi clone) control
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Kev888
- So far gone I'm on the way back again!
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Re: Inline chiller (maxi clone) control
Unless someone is already familiar with this cooler, we may need some pictures again - I'm struggling to work out what the internal configuration is.
In general though, it is possible to bypass in-built thermostats with electronic ones. I've done this both to replace broken stats and also in order to raise the bath temperature; there is a maxi 110 currently maintaining my FV's fermentation temperature whose bath is set to 16c for example.
At warmer temperatures you don't get the ice bank forming or course, so the compressor runs more often (for shorter periods) than it would normally. But this is still infrequent in home-brew situations - and of course a compressor delay on the thermostat will help prevent excessively quick on/off cycling in unusual circumstances.
In general though, it is possible to bypass in-built thermostats with electronic ones. I've done this both to replace broken stats and also in order to raise the bath temperature; there is a maxi 110 currently maintaining my FV's fermentation temperature whose bath is set to 16c for example.
At warmer temperatures you don't get the ice bank forming or course, so the compressor runs more often (for shorter periods) than it would normally. But this is still infrequent in home-brew situations - and of course a compressor delay on the thermostat will help prevent excessively quick on/off cycling in unusual circumstances.
Kev
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guypettigrew
- Even further under the Table
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Re: Inline chiller (maxi clone) control
This may or may not be of any help to you.
My FV is a SS Brewtech 7 US gallon chronical. It's fitted with the cooling coil and heat pad controlled from the SS controller.
Cooling is provided from my Maxi 110. The way I do it is a bit complicated, but works really well. The pump which comes with the SS kit is controlled by the SS controller. When the temperature in the FV gets too high the pump is switched on. It pumps water through the internal cooling coil in the maxi, then through the coil in the FV, then back to the pump and round through the internal cooling coil again.
The Maxi 110 is always on and so the internal thermostat keeps a permanent ice bath. The water going into the cooling coil in the FV is at about -0.4C, so the cooling effect is very fast.
This avoided me having to bypass any internal thermostats in the Maxi and then set up an alternative control system. The controller supplied by SS Brewtech is really good and controls the fermentation temperature to +/- 0.5C.
And, as everyone will tell you, controlling the fermentation temperature has hugely improved my beer.
Guy
My FV is a SS Brewtech 7 US gallon chronical. It's fitted with the cooling coil and heat pad controlled from the SS controller.
Cooling is provided from my Maxi 110. The way I do it is a bit complicated, but works really well. The pump which comes with the SS kit is controlled by the SS controller. When the temperature in the FV gets too high the pump is switched on. It pumps water through the internal cooling coil in the maxi, then through the coil in the FV, then back to the pump and round through the internal cooling coil again.
The Maxi 110 is always on and so the internal thermostat keeps a permanent ice bath. The water going into the cooling coil in the FV is at about -0.4C, so the cooling effect is very fast.
This avoided me having to bypass any internal thermostats in the Maxi and then set up an alternative control system. The controller supplied by SS Brewtech is really good and controls the fermentation temperature to +/- 0.5C.
And, as everyone will tell you, controlling the fermentation temperature has hugely improved my beer.
Guy