Temp control for fermentation

[Chrissparky]

Hi
I'm surprised no one seems to have come up with a plug in fermenter with heating and cooling control built in. In this day and age surely this could be done at a reasonable price. Where you just set the temp on the controller and away you go, no other kit needed.
It would be a great bit of kit for people with not much space like me. Anyone know of anything like this?

 

[Slid]

Hi
I'm surprised no one seems to have come up with a plug in fermenter with heating and cooling control built in. In this day and age surely this could be done at a reasonable price. Where you just set the temp on the controller and away you go, no other kit needed.
It would be a great bit of kit for people with not much space like me. Anyone know of anything like this?

I agree, but point out that those pesky laws of thermodynamics are going to push you down the brewing fridge route in the end. Even in this day and age.

 

[Chrissparky]

I was thinking it could be done with thermo electric coolers and a small immersion heater. Probably not very efficient

 

[ericmark]

The heating can and by some is done with an immersion heater really designed for fish tanks, they do work with a fermentor so I am told.

The cooling is more complex, the problem is the fermentation produces heat, this means if you insulate the fermentor it will over heat, some way some how heat needs to be removed, be it simply into the low ambient temperature of a room, or to the low ambient temperature of a refrigeration unit or to the low ambient temperature of a cooling liquid.

It is possible that you could have a solenoid, which as the temperature rises allows a cold water supply to flow through a heat exchanger within the fermentor. The problem is getting a cold water supply which is cold enough to do the job year round. Although in some areas the supply may be cold enough, it is not always cold enough. So even is circulating cold water is used, that cold water supply needs to come from a refrigeration unit.

Clearly you don't want to be cooling the centre of the fermentor only to have the heat return through the outer skin of the fermentor. So a fermentor using a heat exchanger would need an insulated wall, but that fermentor would be no good where you had no refrigerated water supply. So it would be a rather specialised unit, and not cost effective for a 40 pint batch, as size of the fermentor increases so the surface area per gallon decreases so likely you would need a heat exchanger with a large fermentor. But not really with DIY size.

So next look at methods of refrigeration, there are in real terms three methods, Peltier effect, absorption, and the compressor. The Peltier effect, and absorption are not very economical to run, OK for short term use, few hours in the car, or few days in a caravan, but for long term use it has to be the compressor. I do remember in the late 1950's early 1960's my dad buying a motor with an ice box designed to be built into a fridge, and even today you can get commercial units not supplied with a ready made insulated box, but to get one small enough for use with a fermentor of the size used with beer kits, means buying a fridge or freezer and converting it in some way. There is no reason why you should not use an air conditioning unit, but these are much bigger than the simple fridge or freezer.

Although you could have a liquid container inside the fridge or freezer with a pump to circulate as required, that way a small 32 litre fridge or freezer could be used, it is far simpler to just put the whole fermentor inside a fridge or freezer. So for a system that will work anywhere in UK with reasonable efficiency then it is the fridge or freezer. However I am sure there are places where the cold water is always very cold, and in those areas one could consider a simple solenoid allowing water to flow when too hot. But to market such a system would be a problem, one you are wasting water, and two it will only work in some areas.

You can get Peltier units which will cool or heat a liquid, so you could build a unit using the Peltier system. It would need a STC-1000 to control it, plus a pair of four pole relays, two poles to swap positive and negative to heat or cool and one pole to interconnect the two relays so both can never work at the same time and one pole to switch on pump. It would need the Peltier unit and also a pump plus a heat exchanger (length of pipe inside the fermentor) and a tank or reservoir to keep enough liquid in the system with expansion and contracting. And likely a 12 volt DC power supply. I would estimate a unit like this would retail at around the £150 mark ready built which is more than it costs to by a fridge and convert it, so the demand would be low. With such a low demand I would not expect anyone to try marketing one ready built. It would be a cottage industry at best. And not as economical as a converter fridge.

As you can likely see I did consider the idea.

Even the fridge or freezer is not perfect, with the ambient temperature outside at over 14°C you have to use the refrigeration option to maintain the brew at 19°C because the insulation of the fridge or freezer will not allow the heat to escape. I considered automatic methods to open the fridge door to allow the heat to escape, and close it once the ambient air temperature raises. Then I used an energy meter to measure how much power is used. And decided not worth the effort. Yes in the winter months you could use an insulated box and fans which only turn on when required. But why bother, easier just to use a brew fridge.

 

[Chrissparky]

Really good answer. Thanks. I was contemplating just about all the options you gave. My problem is space at the moment. I think I'll have to try and find space for a brew fridge as nothing else would work in the space I'm trying to utilise

 

[Dutto]

In winter, before I bought my brewing fridge, I used either one of these ...

http://www.homebrewcentregy.com/electrim-75-immersion-heater

... or one of these ...

http://www.homebrewcentregy.com/electrim-heating-tray-for-5-gallons

The immersion heater works very well in cold weather because there is no fear of overheating the brew even when well wrapped up to conserve the heat.

I still use the pad when it's cold but I hook it up to the Inkbird STC1000 to control the top temperature of the brew.

With regard to fitting something inside the FV itself I refer you to the numerous "Infection" threads on the Forum. Anything permanently fixed inside the FV would be a magnet for "nasties" and as a result would require some extreme cleaning, washing and sanitising before use. :thumb:

 

[Fil]

there is a product sold commercially just as you describe its been a banner ad on Jims for ages, but now when i could do with it its not there at all and the name is alluding me..

the banner sub heading is 'lager your beers without a fridge or something similar ..

https://www.brewjacket.com/?gclid=CJb__eSn984CFU6eGwodUwMEYw

there you go...

if it works? exists? or is vapourware awaiting preorder financing i have no idea..

 

[Chrissparky]

I've seen this and it says pre order,
Plus it says about $200 I think, which is a bit pricey.
If it worked it would be good though

 

[ericmark]

It seems to use the Peltier effect? The building blocks are sold so you could build your own if you wanted, problem is the US power supply would not work in the UK so you would need another power supply. I will guess on 12 volt DC. Also expensive to run.

Cooling speed varies from 0.25°F per hour to 1°F per hour depending on ambient difference to temperature set. I know with my set up starting at 23.8°C it cooled to 19°C in 40 minutes. So to convert 4.8 / 5 x 9 = 8.64 / 40 x 60 = 12.96°F per hour with a motor using 65W run compared with the Peltier at 95W on cooling (seems 8W on heating). OK my freezer would slow down is it hit the 10°F mark so may be in real terms more like 10°F compared with 1°F, but it does use less power.

Doing the cold crash with the Peltier system could hardly be called a crash it would be so slow, remember 4°C from 20°C is not 16°F it is 28.8°F by which time your at 0.25°F per hour, so around 65 hours so that's two and a half days, can't really call that a cold crash. With the freezer compartment I use then compartment gets a lot colder than the fermentor that drop from 23.8°C to 19°C saw the ambient air in freezer hit 8°C, never tried a cold crash, but likely the freezer compartment would hit -18°C at which point the motor would cut out so without trying it I have no idea how long it would take. But I would guess on around the 5 hours not 2.5 days.

As I said I did consider the Peltier system, because the cold and hot parts are so close together it seemed to me the liquid cooling units were likely the best option so you can mount the Peltier away from the fermentor, as to if you put the cooling pipes on the outside of fermentor or inside similar to a hot coil in a cistern not sure which would be best, inside would be easier to do just a few loops of plastic pipe, but it would require cleaning, outside means less cleaning problems. I would use alcohol as the cooling medium as should it leak then no harm done. The bits are freely available so easy enough to build.

However the fermentor is only just small enough to squeeze into the freezer compartment of my fridge/freezer, so the freezer is only really the thickness of the insulation larger than the fermentor, so in real terms the only advantage of using the Peltier system is you can spread the bits around it is not one compact unit. If you measure the size of the insulating jacket, and power supply and the Peltier unit then there is very little gain. To my mind just keep it simple, and use a brewing fridge.

 

[HebridesRob]

These are the only things I'm aware of

http://www.gotta-brew.com/products/conical-cooling-jacket.html

In comparison, my brew fridge cost about £50 (fridge from charity shop, stc 1000, tubular heater, project box, plugs, sockets, cables, connectors).

 

[ericmark]

These are the only things I'm aware of

http://www.gotta-brew.com/products/conical-cooling-jacket.html

In comparison, my brew fridge cost about �£50 (fridge from charity shop, stc 1000, tubular heater, project box, plugs, sockets, cables, connectors).

I did not know you could get a ready made unit. As said I looked into the idea, and I also considered what I have in stock so to speak.

I have a very small freezer 32 litres and I have considered removing door and converting into a glycol cooling unit. I note it states

Connect the Jacket to your cold water (or glycol) pump

which makes me think in the main people just use water from tap to cool with.:nono:

The main problem is once you put the fermentor in insulation it can't get rid of the heat from the fermentation, So with ambient below 20°C but above 14°C you need a method to remove fermentation heat, which could be a simple radiator the main thing is to be able to turn cooling on and off, it could be as simple as opening the fridge door.

But once ambient exceeds 20°C then looking at refrigeration. So if building a cooling device why make it for non summer use.

 

[HebridesRob]

I did not know you could get a ready made unit. As said I looked into the idea, and I also considered what I have in stock so to speak.

I have a very small freezer 32 litres and I have considered removing door and converting into a glycol cooling unit. I note it states which makes me think in the main people just use water from tap to cool with.:nono:

The main problem is once you put the fermentor in insulation it can't get rid of the heat from the fermentation, So with ambient below 20[/FONT][/COLOR]°C but above 14°C you need a method to remove fermentation heat, which could be a simple radiator the main thing is to be able to turn cooling on and off, it could be as simple as opening the fridge door.

But once ambient exceeds 20°C then looking at refrigeration. So if building a cooling device why make it for non summer use.

Those are pretty new but most conicals seem to have a jacket available. I suppose the easiest way to use these is have a tank of water (or glycol?) with ice in it. I suppose one could put the tank in a fridge of some kind.

I think the brew fridge is by far the easiest solution.

 

[ericmark]

I am sure one could design a really good temperature controller for brewing. Once one has a coolant filled jacket with some sort of header tank one can have solenoids and pumps with a small refrigeration unit, immersion heater and radiator and a PLC or other programmer to select if refrigeration cooling, air cooling, or heating is required. With a 50 gallon fermentor this may be the best method, when selling on a commercial scale the idea of low production costs and consistent results is important. But with a 40 pint fermentor it is hardly worth the effort, my energy meter has never shown even 1 kWh of power used, think that may cost around 16p. So saving money by using an intermediate cooling system rather than refrigeration is hardly worth while.

 

[Mungobiscuit]

Hi
I'm surprised no one seems to have come up with a plug in fermenter with heating and cooling control built in. In this day and age surely this could be done at a reasonable price. Where you just set the temp on the controller and away you go, no other kit needed.
It would be a great bit of kit for people with not much space like me. Anyone know of anything like this?

Struggling with the same question Chris. I have a conical fermenter that also has an optional lid into which is included a stainless steel coil that immerses into the vessel. I'm trying to find a device that can heat/cool circulated water that could be used for this purpose. The separation of the coil from the brew appeals to me to avoid infections and I do have an ink bird but am struggling to find a device to suit.....