My Brewing Fridge

[D C]

Hi all, I have finally completed my Brewing Fridge tonight after a couple of months sourcing the fridge and buying a TC10 and finally buying my 60W tube heater today. Managed to cadge a big section of 5mm mesh fencing off the old bloke next door. And set about cutting it up with my father in-law’s angle grinder (enjoyed that bit :twisted: ). Then measured up and cut a few blocks of wood to support the wire mesh at the front of the fridge. Then installed the tube heater after carefully drilling through the back of the fridge. Going to test it out tomorrow and see if everything works okay! Took a few photo’s for you lot to have a look at (I know you lot like your brew pron!)

Tube Heater in place

Wooden support blocks in place

Wire mesh in place

FV in place to show final setup

Cheers DC :wink:

 

[Wez]

Lovely jubbly :thumb:

 

[Aleman]

Nice work

 

[Screwy]

Looks the goods, when fermenting put your temp probe on the side of the FV mid wort depth and tape a little foam block or insulating material over it for best results.

Cheers,

Screwy

 

[Vossy1]

Nice work D C :thumb:

when fermenting put your temp probe on the side of the FV mid wort depth and tape a little foam block or insulating material over it for best results

or, using a cable gland in the lid, you could dangle the probe in the wort.

 

[D C]

Hi all, Thanks for the replies and the advice regarding where to site the TC10 probe :clap: that was going to be the next question I was going to ask. So which is best inside the FV or outside ? Or is there not a great deal of difference between the two

: DC

 

[Vossy1]

Or is there not a great deal of difference between the two

There's not really that much of a difference. If the probes in the wort it will react more quickly to changes, but the delay between both locations will be minimal....so it's up to you. You could try both and let us know what you find.

 

[ano]

If the probe's in the wort it will react more quickly to changes in the wort... but will react slower to changes in the air temperature, you'll have a greater lag between the heater coming on and the wort warming up say, meaning the heat's still on when you've got enough energy in the system to warm the wort up sufficiently, overshooting the temp... in practice that might not happen I suppose.

The way I had it in my head was that you'd keep the ambient temperature at a certain temp and have another probe in the wort to make sure it stayed around the temp you wanted it to.

In practice if you're fermenting indoors (As opposed to the shed) do you need a heater?

 

[Vossy1]

If the probe's in the wort it will react more quickly to changes in the wort... but will react slower to changes in the air temperature, you'll have a greater lag between the heater coming on and the wort warming up say, meaning the heat's still on when you've got enough energy in the system to warm the wort up sufficiently, overshooting the temp... in practice that might not happen I suppose

In practice this does not happen. It takes a great deal of ambient heat to change the temperature of 20+ ltr of liquid, and the wort does not overshoot by more than say 0.1 deg.
I have tried the method screwy describes above, insulating the probe on the outside of the fv with a block of foam, and as such it's not responding to ambient air temps, as it's insulated from the environment, within reason. It has the advantage of not having to cut a hole in your fv lid though.

An ATC can only control within 1 deg c +/-, however the TC can control within a 10th of a deg. The only concern I can see with such accurate control of the TC is switching your cooling compressor on too frequently, could reduce it's life. If it's not set to come on frequently I can't see it coping with very accurate temp changes...
I'd be interested if anyone out there has any feedback on using the TC 10 to maintain very accurate temps. I also wonder if such accurate temp regulation is required :hmm:

The way I had it in my head was that you'd keep the ambient temperature at a certain temp and have another probe in the wort to make sure it stayed around the temp you wanted it to.

Assuming no massive changes in temps ie, indoors, then you'd need 2 controllers, when you really only need one. If you were fermenting in a shed which goes below freezing, or gets very cold, then it would probably be a good idea to have some form of environment control

In practice if you're fermenting indoors (As opposed to the shed) do you need a heater?

As the fermentation comes to an end the temperature will drop off quite quickly. If it gets too cold the yeast may become dormant before they've had chance to mop up by-products of fermentation, eg, diacetyl. Another reason to have heating is that as the yeast slow down you may not have hit your target FG. Again if the temp gets too cold the yeast may become dormant, meaning you will not drop the last few points (well not very quickly anyway)

EDIT The comment regards the compressor above assumes using a fridge. This would not be an issue when using a beer cooler where the compressor has been wired independently from the python pump

 

[Aleman]

If you are heating and cooling your wort directly i.e. with a heater and cooler in contact with the wort you want the probe measuring wort temperature. . . . If you are heating the air around the FV . . . then you need to have the probe in the air . . . or possibly in a small volume of water (20-30ml) to smooth out temperature changes. . .. You might want a thermometer probe in the wort to check that fermentation temperature 'follows' the fridge ambient though, as it can be higher than what you have set during the really active phase of fermentation, then approaches the ambient as the rate of fermentation tails off.

As for 0.1C accuracy . . . I go for a 1C swing and while I do not have the requirement for 0.1C control its useful to have it

 

[Vossy1]

As for 0.1C accuracy . . . I go for a 1C swing and while I do not have the requirement for 0.1C control its useful to have it

A, is that 1c +/- or 0.5 +/- that you use? If 0.5 do you use a cooler, and again if so how often does the compressor come on in comparison to 1c +/-?
Ive still got a hankering for a TC 10 :P

 

[Aleman]

My TC 10 controls my Kegereezer . . and IIRC its set to -0.3/+0.7 . . . with a 2 minute delay on the cooling line to save the compressor

 

[ano]

That makes sense cheers Vossy1, specific heat capacity of 20+litres of wort compared to about the same of air is quite a lot more you're right heh.

The thing I was describing was one controller for ambient, and a temperature datalogger in the wort to see how far the temperature of the wort moved, it wouldn't be hooked up to a controller as well. Which I think is what Aleman was alluding to too. But perhaps overkill as you say if it doesn't overshoot by more than 0.1 degrees.

Final question, could you use PID controllers to minimise/prevent the overshoot?

 

[jamesb]

In practice if you're fermenting indoors (As opposed to the shed) do you need a heater?

Not everyone has (or wants) central heating. It was roughly 8degC in my house for months last winter.

 

[jamesb]

Final question, could you use PID controllers to minimise/prevent the overshoot?

I don't fancy using a PID on a fridge compressor, you'd probably kill it.

 

[Vossy1]

The thing I was describing was one controller for ambient, and a temperature datalogger in the wort to see how far the temperature of the wort moved, it wouldn't be hooked up to a controller as well

Ah, I get ya. What Aleman said was correct. From personal experience at times the fv can be 5 deg over ambient, simply due to the yeasts activities :shock: