Advice needed on bypassing thermostat on fridge for kegerator

[Paulmc]

Hi!

I have a wine cooler which I'm wanting to turn into a kegerator. It advertises that it goes down to 4 degrees but it never quite hits that mark. Usually about 7 degrees. I've had a look and the sensor is on the top panel, so it looks like I can maybe bypass this by shorting it and then using an ITC-308 to power the fridge with thermometer in the fridge and I'd be connecting the heating side to a tube heater (I want to also use it as a fermentation chamber when I don't have kegs).

I also have an STC 1000 as my long-term solution for this but I wanted to use the 308 first to see if I can hold this fridge at steady temps. I'm not too hot on how the wiring will work for the STC 1000 yet, either.

This is the diagram for the fridge. Am I right in thinking the blue wires at the sensor top right are the ones I need to bypass in order to keep the compressor running?

Any help greatly appreciated as I'm a little lost with this.

Thanks!

 

[Spoon]

Leave the built in thermostat alone and just wire the mains plug into the stc so it switches the fridge on and off, then set the fridge to a temp below what you want the beer at.

Shorting it might work too though.

If you were feeling clever you could wire the stc to feed power directly to the compressor and remove everything else. But wiring the stc to just switch the whole thing on/off is simpler and means you can always return it to being a fridge by putting a plug back on it.

Cut the mains cable plug off (unplug it first!) Strip a bit back and connect the brown wire to the output of the cooling relay, sacrifice another old mains lead and put its brown to the input of that relay. Bridge from there to the input of the heating relay and live power to the stc.

Connect the blue wires in the two mains lead together in the neutral power connector of the stc.

When you add a heater put the blue wire with the other two (gets a bit crowded so make sure they're secure). And the brown wire to the output of the heating relay.

 

[Bigcol49]

Hi @Paulmc
I think, as the blue wires are connected to the display board, this may simply be the temperature sensor for the LED display.
Try cutting one of the wires - you can always join them later if it doesn't work.
I tried to find an online manual, but the download version was in Finnish!
If your model is the same as the one in the manual, there are buttons for white wine, red wine and a manual setting - have you set the cooler to its lowest setting using the manual button?
Worst case scenario - you will be serving beer at 7°C - not bad! This makes interesting reading.
When you come to wire up your STC-1000 this diagram will help - it's very fussy but it works.

 

[Leon103]

Beer at 7c is fine

 

[Simonh82]

Can you locate the temperature sensor? I know it's a different kettle of fish but I fixed a boiler cut out issue by moving the sensor away from the base and controlling it independently. If you could move the sensor away from the cool interior of the fridge you would be able to use the Inkbird/STC to control the temperature.

 

[Paulmc]

Beer at 7c is fine

Is it? I was under the impression from a lot of sources that kegged beer definitively has to be dispensed at 3.33c and that a tap tower would need to be around this temperature too to avoid foaming. I've certainly not tried this, if it's 7c do you just pressurise to compensate? Hopefully I can still get the fridge lower but would be good to be able to dispense 'hotter'

 

[Paulmc]

Hi @Paulmc
I think, as the blue wires are connected to the display board, this may simply be the temperature sensor for the LED display.
Try cutting one of the wires - you can always join them later if it doesn't work.
I tried to find an online manual, but the download version was in Finnish!
If your model is the same as the one in the manual, there are buttons for white wine, red wine and a manual setting - have you set the cooler to its lowest setting using the manual button?
Worst case scenario - you will be serving beer at 7°C - not bad! This makes interesting reading.
When you come to wire up your STC-1000 this diagram will help - it's very fussy but it works.
View attachment 13473

Thanks Bigcol and Spoon for your helpful replies - I'll try setting up the STC this weekend and hopefully will work well!

I have indeed tried setting the fridge down to the lowest setting of 4c. The built in temperature display shows it's hitting 4 but it never does, I think the compressor is being turned off well before it gets the chance. Knowing it's designed to be down at 4 was what sold me on it originally, so should be good when overriding it.

 

[Paulmc]

Can you locate the temperature sensor? I know it's a different kettle of fish but I fixed a boiler cut out issue by moving the sensor away from the base and controlling it independently. If you could move the sensor away from the cool interior of the fridge you would be able to use the Inkbird/STC to control the temperature.

This is worth a try! I'm not sure where the temperature sensor is actually located now, but I like your thinking

 

[Fil]

you can serve even a highly conditioned beer at a slightly warmer temp if you adjust the serving pressure and your post keg pressure reduction to match. a kegging chart is a good reference.. https://www.google.co.uk/url?sa=t&r...=xbA22cKg6g1riDhoRe225w&bvm=bv.58187178,d.ZG4

 

[Fil]

however to achieve the desired result I would suggest you bypass all/most of the internal circuitry which will mean the loss of the inside light.. and simply provide the compressor with a switched feed from your stc1000 controller.

the diagram in the 1st post indicates that the blue/neutral line is switched to control the compressor?? my limited understanding as a brewer is that normally the current to a device is switched on the live side??

But assuming the diagram is correct then you should be able to use your stc1000 cooling relay terminals to break the neutral feed to the compressor and control it that way.

the cooling relay is issolated from the heating relay and control circuitry sufficiently to allow this afaik BUT I AM NOT AN ELECTRICIAN.