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WikdWaze
09-03-2004, 06:38 PM
Does anybody have any experience with those external thermometers used to control the temperature of a refrigerator? That looks like the only way I can reliably maintain the fermentation temperature since our A/C is broken. What I'd really like to know is whether it would work on a freezer as well as a refrigerator. I had another mental lapse and was looking all over for a small fridge I could get cheap, meanwhile there's a completely unused chest freezer sitting in the kitchen. I don't see any reason why one of those controllers wouldn't work on a freezer, does anybody else?

Derf
09-05-2004, 08:56 AM
Why don't you just stick a thremometer inside and toy with the setting untill it's where you like it? Then it will try to maintain that temp when you have your batch in it.

(Maybe I'm not understanding what you have in mind.)

Jmattioli
09-05-2004, 09:09 AM
Derf,
Unfortunately that won't work as the thermostats that come with the refrigerators won't regulate in the range he needs. I have heard of others who use buy a thermistat that will regulate in that range and turn off the AC when the temperature reaches the setpoint but have no personal experience with the installation procedure.
Joe

JamesP
09-05-2004, 09:44 AM
WikdWaze,

since you are claustrophobic, think outside the box . . .

and sit your carboy in a container of water and drape some cloth over the carboy and into the water.

The evaporation of the water cools down the carboy.
And if that isn't enough, 3/4 fill some plastic bottles with water and get them freezing, then sit the frozen bottles in the water that the carboy is sitting in.

A fan also aids in the evaporative cooling.

If the primary fermenter is a bucket, then you can sanitise the outside of the plastic frozen water bottles, and place them directly into the must (keeping an eye on the temperature of the must).

Of course this isn't quite as automated as what you are after :-/

Oskaar
09-05-2004, 11:25 AM
I agree with Derf, see my previous post:

http://gotmead.com/cgi-bin/yabb/YaBB.pl?board=yeast;action=display;num=1093467409; start=7#7

Oskaar

WikdWaze
09-05-2004, 02:13 PM
WikdWaze,

since you are claustrophobic, think outside the box . . .

and sit your carboy in a container of water and drape some cloth over the carboy and into the water.

The evaporation of the water cools down the carboy.
And if that isn't enough, 3/4 fill some plastic bottles with water and get them freezing, then sit the frozen bottles in the water that the carboy is sitting in.

A fan also aids in the evaporative cooling.

If the primary fermenter is a bucket, then you can sanitise the outside of the plastic frozen water bottles, and place them directly into the must (keeping an eye on the temperature of the must).

Of course this isn't quite as automated as what you are after :-/I like it, but it wouldn't be accurate enough. The yeast I'm going to use needs to stay in the 70-75 degree range. There's no way such a simple evaporative cooling system could keep it in that range. Same with the thermostat in the freezer, it isn't designed to operate in that range, so it wouldn't do the job.

yabb_unknown_usr
09-07-2004, 10:53 PM
Yes, I've used the external thermostat with a chest freezer. It works fine. The only problem is that it seems to make the freezer work harder, though I don't know why that would be the case. The last chest freezer that I used mine on gave up the ghost after about a year and a half, but the chest freezer that I use as an actual freezer has been chugging away for 20+ years. Anecdotal evidence perhaps, but there you have it.

On the same subject, however, you may want to try building one of these:
http://home.elp.rr.com/brewbeer/chiller/chiller.html
I've been meaning to build one for the last five years or so and haven't gotten around to it. Doesn't look too difficult...

Hope this helps,
David

WikdWaze
09-08-2004, 02:29 AM
That chiller is an interesting concept, but I'm not sure it's worth the effort. Unless you have a fairly large icemaker at home you'll spend more money on bag ice than you would on electricity to run a small refrigerator.

JamesP
09-08-2004, 04:33 AM
The following is my understanding of why an external regulator (break the power part-way through the freezer's cooling cycle) will reduce the life of a freezer. You will need to verify this.


When the pump is pumping the gas to do the cooling, it pressurizes the gas. If you stop the pump (the external regulator kicks in), but don't allow enough time for the gas pressure to dissipate, then restarting the pump will put stress on the pump, because it starts up "under-load", resulting in early failure of the pump.


This doesn't mean you can't use an external thermostat/regulator. It just means that by ensuring that there is sufficient time between "switching off" and "switching on", you should reduce the wear on you freezer.

I don't know how long it takes for the gas pressure to return to normal :-/

WikdWaze
09-08-2004, 03:41 PM
The following is my understanding of why an external regulator (break the power part-way through the freezer's cooling cycle) will reduce the life of a freezer. You will need to verify this.


When the pump is pumping the gas to do the cooling, it pressurizes the gas. If you stop the pump (the external regulator kicks in), but don't allow enough time for the gas pressure to dissipate, then restarting the pump will put stress on the pump, because it starts up "under-load", resulting in early failure of the pump.


This doesn't mean you can't use an external thermostat/regulator. It just means that by ensuring that there is sufficient time between "switching off" and "switching on", you should reduce the wear on you freezer.

I don't know how long it takes for the gas pressure to return to normal :-/That's interesting. I was trying to figure out how it could shorten the lifespan of the freezer. I'm still not clear on how that's any different than the normal cycle of a freezer, though ??? I suppose as long as there's enough lag time between cutting off and starting back up, it shouldn't be too much an issue. I'd be in trouble if I broke a brand new freezer :o

yabb_unknown_usr
09-08-2004, 11:17 PM
That chiller is an interesting concept, but I'm not sure it's worth the effort. Unless you have a fairly large icemaker at home you'll spend more money on bag ice than you would on electricity to run a small refrigerator.

Ah, I think you didn't read it close enough. You use gallon milk jugs filled with water and frozen...

It's also much more light and portable than a fridge/freezer, which is a plus for me because I never know where I'll be fermenting (my wife likes to rearrange stuff a lot)...

WikdWaze
09-09-2004, 02:27 AM
Ah, I think you didn't read it close enough. You use gallon milk jugs filled with water and frozen...

It's also much more light and portable than a fridge/freezer, which is a plus for me because I never know where I'll be fermenting (my wife likes to rearrange stuff a lot)...

Oops, I did miss that part :-[ That certainly makes it a better option, but I already have a chest freezer that isn't being used. I could spend $50 building another contraption to take up space in our 900 square foot house, or I could spend $50 to adapt the contraption we already have. If I didn't have the freezer, I would definitely build that chiller.