Temperature Control

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ssashton

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Hi Guys and Gals,

I'm curious, how do each of you control temps during fermentation and also conditioning? Just changing rooms?

My cellar is not very deep so in the summer (like now) it can be as warm as 20C (main rooms 24C). Also I have noticed that even in a cool room, during fermentation, the liquid temperature can be well above ambient say 22C while room at 19C.

I do not have space for a dedicated fridge. So being an engineer I built a kind of temperature control device mostly using PC water cooling components. Water pump, coolant loop, peltier cooler or resistive heater and some micro-controller brains.

If I posted details about how I built it, would you be interested in making our own?

I was considering making a kind of DIY kit that can either warm or cool beer during fermentation and conditioning but would like to know if there is interest.

Mostly I built mine because my cellar is rarely lower than 16C but conditioning is often said to be done around 11C, so I can chill it down with a blanket around the keg. I later found I can place the fermenter in the cellar (usually too cold for fermentation) and then use a resistive heater to maintain a steady 19C liquid temp as per my fav recipe. While the main rooms are too warm.

Yes I'm aware of the 'Brew Jacket', and this would be more Do It Yourself and affordable - some tubing, pump, power supply and instructions. Any interest?
 
Before I got the Brew Fridge I used:
  • The contraption (see photographs) with manual temperature control. I switched bulbs on and off to keep within 3*C before I could afford an STC 1000 and a Tube Heater.
  • A Heat Pad whilst Contraption was in "Carbonation" service.
  • A Trug and Aquarium Heater when I needed more brews on.
The thing to note is that they were all "Heaters".

If you don't have a fridge just use "time" to carbonate and condition your brews. It worked for well over 1,000 years!

Warm weather in the UK is very rare and until WW2 there was NO chilled beer sold in the UK. There is nothing wrong in drinking beer at a couple of degrees below room temperature; although lager can be much improved by chilling.

Contraption 2.jpg
Contraption 3.jpg
 
I was considering making a kind of DIY kit that can either warm or cool beer during fermentation and conditioning but would like to know if there is interest.

If you are going to make the DIY kit then post instruction fine if you intend to sell please read this -

THBF Sponsor Membership (Monthly)
(Scroll to bottom of page)

https://www.thehomebrewforum.co.uk/account/upgrades
.
 
I admire anyone who has the ability or desire to build such a temperature controller, but I couldn't, so for £10 I would just buy one from Amazon (other sources are available). A small fridge isn't much bigger than the FV and you can store the empty FV in it when not in use to save a bit more space if needed. I wonder how I managed before I had the fridge even for controlling heating, let alone chilling.
 
Using a fridge or freezer is a great way to do it especilly combined with a thermostatic controller like the W1209. I wasn't very successful at finding a small one that would fit a keg or fermenting bucket easily though - most had a big lump in the bottom shelf area or have a chiller section in the top corner, or both. So it seems like the fridge would need to be a fair bit bigger than the keg which I don't personally have much room for.

ycpx4D3.jpg


If there were interest I would probably tidy up my design and publish an Instructables article on how to make your own, and if people like that maybe offer a kit of all the bits to make a little pocket money (at which point I would certainly become a supporting member here). Right now I'm just wondering what you guys do and whether something compact with both cooling and heating capability is even desired.
 
I have 3 beer fridges at the moment but before I had the space I would use a Builders bucket filled with water and some Ice blocks added to the bucket and also a fan aimed at the FV, it all worked well but was a continuous checking reageme where now I don't need to.
 
I'd certainly be interested in a diy peltier system.

I currently just use a heat belt and an inkbird controller on my fast ferment, but I'm looking at upgrading to a stainless steel bucket, and have seen various conflicting advice about heat belts (I'm not overly concerned about an earthing issue, but I don't know if you could induce a current in the stainless steel and get a shock that way?). I thought about using the cooling coils and a pump in some ice water but constantly topping a bucket up with ice seems faffy and messy. I had looked at the brew jacket peltier but it's a bit costly!

I've reflashed an stc1000 with the stc1000+ firmware (building it into a box is currently on the to-do list!), so if there were a way to incorporate that (i.e. 2 power sources for heating and cooling) that would be handy. Otherwise I'd probably just built the peltier bit and skip the resistance heater.

What pump / cooler did you use for yours?
 
You can get them a lot cheaper than that. It was just the first link I found.
 
This is my, just finished, ferm fridge. Total cost circa £25. STC100 and a 30w tubular heater, fridge picked up from roadside!! Works fine, just needs a good scrub! Not huge, but fits the 30l square food grade containers I now favour for primary ferm.
 
Yes I'm aware of the 'Brew Jacket', and this would be more Do It Yourself and affordable - some tubing, pump, power supply and instructions. Any interest?

Do you have any pictures of your setup?

I was thinking about one of theses
Hilitand 12V Thermoelectric Cooler Peltier Semiconductor Refrigeration DIY Water Cooling System Cooler Device with Fan https://www.amazon.co.uk/dp/B07DVJRFXN/ref=cm_sw_r_cp_tai_yD5jDbX5ZM5Y8
Or these
12V 4-Chip Semiconductor Refrigeration, TEC1-12706 DIY Thermoelectric Peltier Air Cooling Device Cooling Fan https://www.amazon.co.uk/dp/B07MQBGG8R/ref=cm_sw_r_cp_tai_SE5jDb4X69RQQ

Connected to a power supply like this.
KINGPRINT DC 12V 30A 360W Universal Regulated Switching Power Supply for 3D Printer, CCTV, Radio, LED Strip Lights, Computer Project https://www.amazon.co.uk/dp/B079BR75SF/ref=cm_sw_r_cp_tai_rF5jDbAJ98KVY

Then a cheap submersible pump to circulate it all.

Does that sound about right?

Could you use a second peltier pad the other way round for he heating side?

Do you use water, or glycol / ethanol / vodka as a refrigerant?
 
Sorry I didn't see all these replies.

This is what I have done for the moment:

W1209 thermostat PCB (comes with temp sensor)
12V 200watt PSU
TEC 12706 (60watt) Peltier
12V diaphragm pump (high pressure)
CPU Water Block
CPU Cooler

The W1209 temp sensor is tapped to the side of the keg and the keg is wrapped in a baby duvet for insulation and also sitting on top of insulation.

The W1209 in 'cooling mode' switches on a relay to power the peltier and pump when the temperature rises above the set point. It can also be switched to 'heating mode' and will switch the relay when the temp drops below set point.

The water loop is a closed loop that goes in to the keg through some fittings in the top and simply loops around a few meters of tubing inside, then comes back out to be chilled again. I manage to drop about 8C below ambient.

It's worth noting that a peltier cold side will become the hot side if you simply invert the power connections. So in that way an appropriate controller could switch from cooling to heating just by reversing the connections.

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I also fitted a Schrader valve (tyre valve) so I can measure the keg pressure.

I would change this a little bit if doing it again. Firstly it seems like ready assembled water block / peltier / coolers are available like the one Pottsworth linked above, which would make life easier. I've just bought one to try* that is meant to be 180watts. However, in the past I bought a supposed 15-Amp peltier from ebay and it was just 6-Amp item re-badged. So I'm going to test the assembled unit and see how much power it is really drawing.

* https://www.ebay.co.uk/itm/113779944099

The pump I used is a diaphragm type designed for creating high pressure (~100PSI) and it adds quite a bit of its own heat to the fluid. I had it in my parts box so that's why I used it. I think I'd try a PC water cooling pump in the future, but be aware you may need at least some reasonable pressure to pump fluid around meters of thin tubing.

Plastic tubing doesn't transfer heat out of the keg well (hence I used a couple meters of it coiled up). I think I would insert a few aluminium sections in the keg side. Do not use copper, I gather it reacts with carbonic acid.

If you keg doesn't have a large enough top to get fittings in here, it would be necessary to wrap the tubing around the outside and in that case insulation i even more important.
 
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P.S. In the winter I wanted to keep constant temps in the fermenter bucket so I placed it in the cellar which was around 14C and replaced the peltier with a couple of power resistors to heat the water loop. It worked very well keeping 19C within +/- 0.1C.
 
If you had something like an inkbird controlling the temp (i.e. something with a heating and cooling circuit) - do you reckon you could have 2 PSUs wired in opposite directions through the peltier (or potentially even 1 PSU and relays to switch polarity), then use the same peltier for both heating and cooling?
 
Just thinking out loud here.

I don't know about the InkBird but if I made this as a DIY kit I would use an Arduino. A single power supply could be used and a double pole relay could wire the peltier in cooling mode or reverse the connection for heating. It is as simple as switching the wiring direction.

A simple bit of code could read the temp sensor and switch the relay appropriately. You could have a little OLED screen to display current temperature and set point. If you wanted to get fancy it could connect to the internet on wifi and send data to your phone such as average on time and power consumption per day etc.. I'm not sure anybody really needs that though!

I got that 180watt cooler unit today. It's only 100watts. The Peltier unit as a TECooler HT064141 and the data is actualyl avilible for it here: http://pmoa89152.hkpic1.websiteonline.cn/upload/tecoolerproduct.pdf

Rated at 8.8Amps at 15V (132watts). Which is 100watts at 12V.

I'm running at 14V and got 8A, so the data is good, but the people selling these assembled units are just trying to gouge a profit. anyway it's still better than the 60watt one I currently use.

It's a shame I see no way of telling which sellers will really give you the Peltier they say on places like eBay and AliExpress. You could buy from a trusted supplier like RS Components but instead of £8 for a peltier you'll be spending £35-40.

I'm not sure if the heat-pipe type heatsinks will allow a reversed connection situation though. If you setup like this, the heat going to the liquid side is being drawn from that 'heatsink'. If it can't keep drawing heat from that heatsink because the heatpipes don't work, I've no idea if the hot side will keep putting out heat. Heat-pipes are unable to 'work backwards' they expect the bottom to be hot and the top to be cold and I'm not sure how they might behave at really cold temperatures ,the gas inside might jut stay liquid all the time. Better to have a solid traditional heatsink if you plan to use the peltier both ways around.
 
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I guess at least you are still getting more wattage per £, even if not exactly what you expected!

That currently sounds a bit beyond my level of Arduino experience, but well within the capabilities of the “learn Arduino” kits, so when I get those few free days maybe I’ll finally get around to working through one!

That makes sense with the heat sink. Presumably there’s an even worse risk that if you pull enough heat through the heat sink you could even freeze the liquid in the pipes?
 
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