Conditioned Fermenter "Chamber"

Hey all,

I was wondering if anyone uses a special container for maintaining the exact (or rough) temperature you desire for fermentation?

I keep my house at 75 F and didn't want to lower it, so I made a 2L x 2W x 3H feet fermentation chamber out of 3/4 inch insulated sheeting, doubled up to make 2-ply 1.5 inch walls. I went to an electronic parts store and got everything to make a home-made thermostat to power a peltier cooler with heat synchs and fans for circulation. This was mounted on top.

You can see pictures here. (Still need to dress wires properly

I have been keeping the temperature inside the chamber at a constant 69 degrees, but it can easily go lower.

Just wnated to share my method, and was wondering if anyone has done anything similar?

- Bill

I've just got an old fridge in the garage with an external thermostat. Since the weather here seems to fluxuate a lot and my garage is not well insulated or heated, I have to be careful about the carboys getting too cold at night or on colder days when the outside temp is below 60 degrees.

To deal with temp drops, I have an old lamp in the fridge with a 20W lightbulb in it that I leave on all the time when it's cold. This way it never gets too cold or too warm inside the fridge, even if the outside temp drops to freezing or rises up to 100 degrees.

Ideally, I would like to have the lamp on a second thermostat so that it only turns on when the temp drops too low, but I haven't had time to actually do this yet.

-walker

Very cool... what was the parts total?

A lot of people build fermentation chillers, but they're a lot smaller than yours, and usually cooled by ice blocks. How much did that peltier cooler run you?

Well, I'm not sure what 'billism' is, but your website is filtered as 'pornography' here at work so I'll have to check it out when I get home. Sounds very similar to the Son of Fermentation Chiller: http://home.elp.rr.com/brewbeer/chiller/chiller.PDF

I haven't built one, but am considering it this summer. Your substitution of a peltier cooler for the rather primitive blocks of ice sounds quite intriguing, however! I'll check the link when 'the man' doesn't have his foot on my neck.

What temperature range is that peltier cooler capable of, anyway?

The peltier cooler (with heat synchs attached) was $12.95. The parts for the thermostat were a total of like $55. The most expensive parts were the transformer (for built in power supply), which was $18.95 and the aluminum enclosure, which was $18.50. All other parts are pretty cheap. Oh, and the insulated sheeting was like $10 each I think and I needed 3.

Total cost of about $90.

My father, who lives near me, was the engineer for making the thermostat. =) I can supply the schematics if anyone wants them. I found it hard to find a pre-made thermostat for something like this.

BeeGee said:

Well, I'm not sure what 'billism' is, but your website is filtered as 'pornography' here at work so I'll have to check it out when I get home. Sounds very similar to the Son of Fermentation Chiller: http://home.elp.rr.com/brewbeer/chiller/chiller.PDF

I haven't built one, but am considering it this summer. Your substitution of a peltier cooler for the rather primitive blocks of ice sounds quite intriguing, however! I'll check the link when 'the man' doesn't have his foot on my neck.

Click to expand...

porn? I have no porn on my site. I do drop the F bomb (rarely, though) when warranted. It is my personal web site.

Ice. wow. I don't think I would want to fool with that. Peltier coolers are great. Though quite power enificient, they do the job very well. My brother calculated it out and it probably costs about $3 a month to run it with teh fans if power is 14 center per kWh.

bobbyc said:

What temperature range is that peltier cooler capable of, anyway?

Click to expand...

I am not totally sure. The cool side gets pretty cold from what I can feel. I would guess in the lower 50s, maybe 40s. I have no way of really telling for sure right now.

I was kind of shocked and happy to find a peltier cooler with built-on heat synchs.

Hey billism, where'd you get the parts...EPO?

Could you PM me your address, and leave your back door unlocked so I can come over and borrow that thing, ninja style?

El Pistolero said:

Hey billism, where'd you get the parts...EPO?

Could you PM me your address, and leave your back door unlocked so I can come over and borrow that thing, ninja style?

Click to expand...

Yea, EPO. Gotta love EPO.

I didn't think ninjas needed doors to be unlocked.

billism said:

I am not totally sure. The cool side gets pretty cold from what I can feel. I would guess in the lower 50s, maybe 40s. I have no way of really telling for sure right now.

Click to expand...

So you could use this for lagering, too?

bobbyc said:

So you could use this for lagering, too?

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Maybe. I don't know how efficient it would be at maintaining an enclosure in the 55 F range. You might have to use 2 peltier coolers. =) This is my first brew ever, and it is an ale.

I converted an old side-by side frige to a fermentation/lagering "cellar":


The right side (fermentation) can hold up to 3 carboys or 1 carboy and some cornies. The left side (lagering) can hold 2 cornies or bottles on shelves and yeast samples.


This is the thermostat that controls the compressor and with it the lagering temperature which I keep between 32 and 34 most of the time


This thermostat controls the fans and with them the fermentation temperature. There are 2 small ones on this side and one big one on the other side.

So far it works pretty well. Bu I haven't tested it in the summer yet. There might be a lot of work for the compressor and fans if the temp in the garage goes up to 80F

Kai

Wow, that is very cool but way over my head. I'd love to see some idiot proof plans for artist types . . .

Walker said:

Ideally, I would like to have the lamp on a second thermostat so that it only turns on when the temp drops too low, but I haven't had time to actually do this yet.

-walker

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It's okay walker you don't need to tell us how 'busy' you are, we all know the real reason is because you're cheap.

Cheyco said:

It's okay walker you don't need to tell us how 'busy' you are, we all know the real reason is because you're cheap.

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Yeah, but I'm an electrical engineer and know that I could make a simple thermostat for a 25W lightbulb for just a few dollars spent at Radio Shack.

In this case, the reason is that I am simply too lazy, I guess.

-walker

Walker said:

Yeah, but I'm an electrical engineer and know that I could make a simple thermostat for a 25W lightbulb for just a few dollars spent at Radio Shack.

In this case, the reason is that I am simply too lazy, I guess.

Click to expand...

I feel the same, I could easily come of with some temperature control that uses a micro processor and has a nice interface with a glowing display. Heck, in my hay-days of building electonic stuff I even made a 300W amp and a digital effect unit (DSP and micro processor) but now I'm just plain lazy and cheap.

I wish I could find cheap (> $10) digital thermostats that have a range of 28F - 70F. None of the AC thernostats go down this low.

Maybe some time, I have the money, time and motivation to pimp this fridge. But before this will happen I need to have a home brew tap system.

ian said:

Wow, that is very cool but way over my head. I'd love to see some idiot proof plans for artist types . . .

Click to expand...

I guess the best idiot proof thing that's out there, is using a fridge or freezer chest with one of these thermostats that you put between the fidge and the outlet. But I was to cheap to spend the $50 for this.

Kai

King Kai said:

now I'm just plain lazy and cheap.

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You've been living in the USA too long, Kai.

Walker said:

You've been living in the USA too long, Kai.

Click to expand...

No.

I've been working in electronics engineering for to long.

Kai

King Kai said:

No.

I've been working in electronics engineering for to long.

Kai

Click to expand...

My problem is that I have been focused on digital electronics and logic design. I can't even remember the last time I biased a transistor or used AC voltage for anything.

I know I'll need a 1 voltage regulator, 1 thermistor, 1 transistor, 1 potentiometer and 1 relay to make a simple low-load controller for my lamp, plus a few obligatory resistors and capacitors, but...

god.. it's been about a decade since I touched any of that stuff. I'm afraid I might burn the house down.

-walker

Walker said:

My problem is that I have been focused on digital electronics and logic design. I can't even remember the last time I biased a transistor or used AC voltage for anything.

I know I'll need a 1 voltage regulator, 1 thermistor, 1 transistor, 1 potentiometer and 1 relay to make a simple low-load controller for my lamp, plus a few obligatory resistors and capacitors, but...

god.. it's been about a decade since I touched any of that stuff. I'm afraid I might burn the house down.

-walker

Click to expand...

What about using a relay?
That's what they used before they had thermistors. And they are much easier to debug and understand than thermistors.
You can operate the relay with a cheap room AC thermostat rated for 30V by using some AC-DC converter that you may have left over from an old cell phone. The relay will do the 110V switching for you . If you use 2 relays, you can even switch the compressor of the fridge with it. But yes, there is some 110V work involved in this and you may want to be careful. If you want to make it as save as possible, put the relays in a switch box used for electrical installation.

Kai

Hey Kai, whan was the coronation?

King Kai said:

What about using a relay?
That's what they used before they had thermistors. And they are much easier to debug and understand than thermistors.
You can operate the relay with a cheap room AC thermostat rated for 30V by using some AC-DC converter that you may have left over from an old cell phone. The relay will do the 110V switching for you . If you use 2 relays, you can even switch the compressor of the fridge with it. But yes, there is some 110V work involved in this and you may want to be careful. If you want to make it as save as possible, put the relays in a switch box used for electrical installation.

Kai

Click to expand...

A relay is a switch that opens and closes based on circuit logic. A thermister is your "thermometer" that changes resistance based on temperature. So the relay is switched on based on the resistance from the thermister, basically.

billism said:

A relay is a switch that opens and closes based on circuit logic. A thermister is your "thermometer" that changes resistance based on temperature. So the relay is switched on based on the resistance from the thermister, basically.

Click to expand...

You are right, I got thermistor confused with a triac.

Kai

King Kai said:

What about using a relay?
That's what they used before they had thermistors. And they are much easier to debug and understand than thermistors.
You can operate the relay with a cheap room AC thermostat rated for 30V by using some AC-DC converter that you may have left over from an old cell phone. The relay will do the 110V switching for you . If you use 2 relays, you can even switch the compressor of the fridge with it. But yes, there is some 110V work involved in this and you may want to be careful. If you want to make it as save as possible, put the relays in a switch box used for electrical installation.

Kai

Click to expand...

I did plan on using a relay, but maybe you have a different idea.

My idea was to use the thermistor and potentiometer in series to adjust my temperature trigger point, tapping the point in between to feed into the transistor.

When the voltage into the transistor was the right level, it trips and allows current to flow through the armature of my relay.

All the above circuitry could run off a low voltage source (like a battery or AC->DC converter and voltage regulator to draw off the 110V line voltage.)

The actual power path through the relay to the lamp would run on 110V.

Something like this (crude diagram with no caps or resistors):

Walker said:

I did plan on using a relay, but maybe you have a different idea.

My idea was to use the thermistor and potentiometer in series to adjust my temperature trigger point, tapping the point in between to feed into the transistor.

Click to expand...

nice drawing

But yes, this should work.

The only thing I would be worried about is the lack of hysteresis. This means that relay might be operating when the transistor is barely on or off. Which burns some power in the transistor, and the relais might be switching more than necessary. With a lamp as the load I don't see a problem, but you shouldn't switch the compressor with this.

Kai

King Kai said:

With a lamp as the load I don't see a problem, but you shouldn't switch the compressor with this.

Kai

Click to expand...

No plans to do that. I already coughed up the $50 some time ago and own a 'nice' external thermostat already that I use to control the fridge's compressor.

I just need something simple (and cheap) to control my puny little heating element.

-walker

King Kai said:

The only thing I would be worried about is the lack of hysteresis. This means that relay might be operating when the transistor is barely on or off. Which burns some power in the transistor, and the relais might be switching more than necessary.
Kai

Click to expand...

Good point, though. I might have to add an opamp or two to the whole thing if I am concerned about this.

Like I said, though... I'm kind of lazy lately, so I'll probably never even get around to making this.

Walker said:

Good point, though. I might have to add an opamp or two to the whole thing if I am concerned about this.

Like I said, though... I'm kind of lazy lately, so I'll probably never even get around to making this.

Click to expand...

That's why I liked using the mechanical room AC thermostats. They have the hysteresis build in, although it may actually to big for my purposes.

You can either use an oamp or add another transistor to implement the hysteresis. But with another transistor you will be getting yourself deep into analog circuit design and will have to do some serious calculations to get it right.

I wish they would sell (cheap) digital thermostat kits on the regular electronics web-pages or Radioshack. This would be much more useful than the common LED X-mas tree gadgets that they have.

Kai

I'll post the schematic when I get home late tonight, or in the morning. I am at work now.