Fermentation Chamber Build - Heat Source and Holes?

Hello all,

I've taken a leap into All-Grain Brewing and Pressure Fermentation. I'm looking at building myself a fermentation chamber. I've sussed out an undercounter fridge on marketplace that should be suitable for my 30L all rounder and should be okay for a 23L carboy with airlock too (we'll see). If this one isn't suitable then I have seen a Kenwood one in Curry's that I could grab too of a similar size
Will be using a RAPT Temp Controller to control it.

Couple of Queries:

1. Could I use a Kegland Heat Wrap Belt as my heat source instead of a tubular space heater?
2. Can I do this without drilling any holes? I don't really want to drill holes in the fridge or cut wires of heaters to pass through these holes if I can avoid it.

If I were to use a heat belt, both the Fermzilla and the carboy would need to use thermowells, easy enough to do for the Fermzilla but would adapt a solid carboy bung to take an airlock AND a thermowell to use. I'm just wondering how this would affect the brew though, having the heat wrap wrapped around the fermenter but the cooling is the ambient air around it. The heating and cooling trace may be a bit wild

aero-spaced-out said:

Hello all,

I've taken a leap into All-Grain Brewing and Pressure Fermentation. I'm looking at building myself a fermentation chamber. I've sussed out an undercounter fridge on marketplace that should be suitable for my 30L all rounder and should be okay for a 23L carboy with airlock too (we'll see). If this one isn't suitable then I have seen a Kenwood one in Curry's that I could grab too of a similar size
Will be using a RAPT Temp Controller to control it.

Couple of Queries:

1. Could I use a Kegland Heat Wrap Belt as my heat source instead of a tubular space heater?
2. Can I do this without drilling any holes? I don't really want to drill holes in the fridge or cut wires of heaters to pass through these holes if I can avoid it.

If I were to use a heat belt, both the Fermzilla and the carboy would need to use thermowells, easy enough to do for the Fermzilla but would adapt a solid carboy bung to take an airlock AND a thermowell to use. I'm just wondering how this would affect the brew though, having the heat wrap wrapped around the fermenter but the cooling is the ambient air around it. The heating and cooling trace may be a bit wild

Click to expand...

There should be enough give in the door seal for the cable to go through to the inside.

Or, if your fridge has is, thread through the drain hole on the back.
(It's not always obvious on new fridges as it's covered with a little cleaner brushy thing with some models)

jof said:

Or, if your fridge has is, thread through the drain hole on the back.
(It's not always obvious on new fridges as it's covered with a little cleaner brushy thing with some models)

Click to expand...

Plus one to this. I fit my thick tubular space heater cable, inkbird probe and usb cable through this, which also helps to keep things neat. The negative is that you will definitely need to cut and re-wire the plug.

I’m interested on hearing thoughts on heat jacket vs space heater. I’m thinking of moving to the heat jacket for my next fermentation chamber, partly due to space and partly due to availability.

I’m firmly in the ‘heat the space’ camp. I prefer to control the air temperature and just monitor the brew temperature. This allows the wort temperature to naturally rise during fermentation and then fall back when it’s over. Set the temperature to the low end of the preferred range and let it do it’s thing.

I use a heat belt for mine. I popped out the condensation sleeve at the back, thinned it out a bit with a drill bit so the cables would fit and ran the heat belt cable & thermostat through it. You could notch the rubber seal on the door but going out the back is cleaner looking.
Be sure to leave a loop pointing towards your condensate tray at the back so drops don't run down the cables.

jof said:

Or, if your fridge has is, thread through the drain hole on the back.
(It's not always obvious on new fridges as it's covered with a little cleaner brushy thing with some models)

Click to expand...

I agree with that, I drilled no additional holes.
The second hand fridge I bought had a hole in the back for connecting the hydraulic circuit inside the fridge to the motor in the back. I was easily able to fit temperature probe and heater cable in that hole.

As an heater, I use an wrap belt.

Just a quick update, the marketplace option fell through so I've purchased new from Curry's.
For those interested (and for the sake of keywords on the search bar) it was a Kenwood KUL55X23 Under Counter Fridge that I'll be using as my fermentation chamber/temperature controlled chamber. Was £149 new so trying to modify it as little as possible.
This does have a drainage hole and I fed an old earphone wire through it and it comes out on top of a drip tray on the back so I'll probably remove the grommet that's already there and add my own to help with the insulation aspect too.
I'll need to make adjustments and rewire my heater plug though. A small price to pay but I'd rather that and be safe in the knowledge that I can just keep this as a normal fridge should I decide to sell it on.

It fits the Fermzilla 30L All Rounder with the ball lock posts on it. Minor positioning adjustments can be made if one were to install a disconnect to it such as keep the fermenter tilted forward at an angle.
Looking at measurements of glass carboys from suppliers, it will not fit a glass carboy but it may fit a PET carboy if it has a blow off tube attached instead of an airlock.

Will send photos in later when I get a chance to get everything into position as I have my RAPT temperature controller on the way. I do not have a carboy so I can not send photos of this, it will only be of my Fermzilla.
Hoping this helps other users as this is something I have noticed that people have been looking for answers like this during my own search.

I think for now I'm going to go with the space heater option. Easy for me to get my hands on one. I can look at other heating options and temperature profiles later. The engineer in me is itching to perfect it but I just need to get it functioning first lol

MrJay83 said:

Be sure to leave a loop pointing towards your condensate tray at the back so drops don't run down the cables.

Click to expand...

Could you explain what you mean by this please? I can't picture it in my head.

It will be too awkward for me to pull it out but think of it like water pouring down one side of a "U". It will drop off at the lowest point and not run up the opposite side. You want to do this "U" into the condensation tray so the water will fall off there and not run all the way down to a plug. Your cables can go whatever way the want after that.
A fair bit of frost builds up on the back wall during a cold crash so don't completely block up the drain.
I used half of the Styrofoam packaging from an Instapot on a couple of blocks of wood. Seems to fit the allrounder perfectly. Like 2/3s of an eggcup.

MrJay83 said:

It will be too awkward for me to pull it out but think of it like water pouring down one side of a "U". It will drop off at the lowest point and not run up the opposite side. You want to do this "U" into the condensation tray so the water will fall off there and not run all the way down to a plug. Your cables can go whatever way the want after that.
A fair bit of frost builds up on the back wall during a cold crash so don't completely block up the drain.
I used half of the Styrofoam packaging from an Instapot on a couple of blocks of wood. Seems to fit the allrounder perfectly. Like 2/3s of an eggcup.

Click to expand...

I'm with you now, I had a feeling that's what you meant but couldn't really be 100% sure. Appreciate the advice!

Twostage said:

I’m firmly in the ‘heat the space’ camp. I prefer to control the air temperature and just monitor the brew temperature. This allows the wort temperature to naturally rise during fermentation and then fall back when it’s over. Set the temperature to the low end of the preferred range and let it do it’s thing.

Click to expand...

Here's wot I done......got a largefridge on clearance from Curry's , got a small tubular greenhouse heater from Ebay, built an STC 1000 into a project box from Maplin's, with two switched 3 pin mains sockets on the top of same. All easy enought o wire, diagrams are easily findable on ye olde 't interweb . The fridge had some kind of sunken area in the bottom , leading to a drain of sorts , likely for when defrosting, although it's a frost-free with no icebox- it's a Beko . This was convenient to run the wires up and into the fridge for the heater , withut compromising the door sealing at all . Likewise, the wire from the STC unit's temp probe was disconnected from the unit- 2 screw terminals on the back - and this was fed thru' a small puncture in the 'fleshy' part of the magnetic rubber door seal from the inside, as the wire is thin , and doing it this way , the hole was kept minimal , rather than feeding in from the outside, as a larger hole would be required for the actual probe on the end of the wire. To all intents and purposes, the door sealing is intact .A wooden shelf was knocked up to sit on the half-depth shelf that existed in the bottom with a couple of legs at the front of the shelf, under which the tube heater sits. , a dozen or so 2 inch holes were made in the wooden shelf with a holesaw. it works a treat, and was pretty cheap to do. See attached pic, might explain it all easier than my words.

This might help. I'm using a rapt pill & controller. So I just put the probe between the polystyrene and allrounder.

aero-spaced-out said:

The engineer in me is itching to perfect it

Click to expand...

You'll get over it, I did .

It's a process you should go through, though, as you learn a lot.

I thought it worthwhile giving another update as this fermentation temp chamber has been a bit of time in the making.
I believe I have finally finished it and will be doing a test with water to get my temp controller settings down to a fine art while I wait for my other items to arrive from AliExpress for my next brewday.

I've attached a photo after a literal month of saying I would.
As you can see, this fridge couldn't be any more perfectly sized for the 30L all rounder. To get ball locks attached I just tilt the all-rounder toward me and voila. I have complete access to them.
I've added a thermowell and I'm a little worried as I may have made the hole to big but this water and pressure test will allow me to see that.

I just built the small wooden shelf tonight after work as I have been itching to try the fridge. I am thinking of leaving the glass shelf in as I forgot to take i to account the thickness of the glass when making my cuts and I don't want to have to spend another 5er on a length of timber and cutting it all again. The glass shelf is fully supported by the wood underneath. It works and that's that.

Will likely absolutely plaster the wood with some yacht varnish after a week or two of the water test to see if there is any moisture gathering near it but mostly.just because I've seen a few loudly rotty horror stories and I've already got the varnish so why not.

There is still a fairly large gap at the door area of the fridge and a small gap between the glass shelf lip and the compressor hump so this should allow for convection. Because of this I am opting to NOT put in any fans.
If I do there are some small dual 40mm USB fans with L/M/H settings costing like 15 quid at most thayt I can add later.

Wire for the tube heater is going out the drainage hole and as I have already had the fridge on and FROSTED at the back I can happily.see that it still has enough of a gap around the cable and the grommet to drain so that's a win.

Temp probe is just fed in through the door as the cable is small enough to not impact it massively.

Will report back in after a week or two of water testing and Temp Controller optimisation.
Happy brewing.

I think you'll struggle to get a spunding valve onto that. I don't use the stand and have some Styrofoam to keep it in place and let it sit down a little.
Chop that float hose down so that it can sit on the bottom with hardly any slack. It's a pain in the *** when it starts wrapping around the thermowell.

MrJay83 said:

I think you'll struggle to get a spunding valve onto that. I don't use the stand and have some Styrofoam to keep it in place and let it sit down a little.
Chop that float hose down so that it can sit on the bottom with hardly any slack. It's a pain in the *** when it starts wrapping around the thermowell.

Click to expand...

This is currently how I'm running with it. (See attached)
Waiting on some Blowtie diaphragm spunds to arrive as this spring one has shown to be incredibly unreliable.
Good shout about the float hose, I hadn't thought about that.

Twostage said:

I’m firmly in the ‘heat the space’ camp. I prefer to control the air temperature and just monitor the brew temperature. This allows the wort temperature to naturally rise during fermentation and then fall back when it’s over. Set the temperature to the low end of the preferred range and let it do it’s thing.

Click to expand...

Where do you put the temperature probe? Presumably not attached to the fermenter or in a thermowell

FYI my set up is very similar had you thought about carbonation cap tee’s they make the fitting of a spunding valve so much easier

Mash Monster said:

FYI my set up is very similar had you thought about carbonation cap tee’s they make the fitting of a spunding valve so much easier

Click to expand...

That is bloody cracking that!!
If you don't mine my asking, what is the height of the T piece when it is attached and in use compared to that of a Ball lock post?

aero-spaced-out said:

That is bloody cracking that!!
If you don't mine my asking, what is the height of the T piece when it is attached and in use compared to that of a Ball lock post?

Click to expand...

The Tee (with a cap on ) is 5-6mm taller than the carbonation cap 46mm v 40mm
Hope that helps