Temperature variation in keezer, solutions?

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McKBrew

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Finally got around to placing my Ranco temp probe in some gel as I've seen in several threads. Before then, I just stuck the probe between the kegs near the bottom.

I let the gel cool overnight in the keezer without the probe in it. This morning my probe (at the bottom) was reading 35 degrees. The gel at the top was around 43 degrees. This tells me that the top of the keezer is warmer than the bottom.

Two things come to mind. 1) Even with a 2X6 collar, a bit more insulation might be needed. (Although it doesn't seem like the compresser cycles much at all. 2) Most refrigerators and upright freezers have a fan to blow air around. Chest freezers on the other hand have no air circulation and rely on being packed full to maintain temp.

Has anyone put a small fan in a keezer to move air around for more even cooling?

Where in the keezer is the best location to put the "gel" bottle for a good reading?

Thanks for the input.
 

humann_brewing

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Sorry I do not have any insight for the location or a fan addition, but I was wondering if you could point me in the direction of the Gel Bottle solution?

Thanks,
 

SpanishCastleAle

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I keep my temp probe (digital thermometer probe) in a jar of water on the compressor hump. It's not as cold there as the back corner (the coldest)...where I put the lagering kegs. Once I placed the collar on mine I'll be keeping 2 serving kegs on the hump...so I can keep certain ales/styles a tad warmer than the other 2 serving kegs (my keezer only fits 4 now...6 with the collar installed). I'm trying to use the temp vs. height difference to my advantage.

In mine the bulb for the temp controller doesn't get any jar or water or anything, it's just exposed to the air just above the hump. Wouldn't want a jar of water 'slowing' it's response and widening the temp swings. Good for the thermometer probe; bad for the temp controller bulb.
 

JesseRC

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i place a large computer fan in there that runs off of an old phone charger pack. Works for me. You will get better results once you fill that baby up with kegs full of gold. All freezers, upright or chest work better when fully stocked. I got the same temp difference on mine , and mine is outside. I aim the fan from side wall to top at faucet shanks.
 
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McKBrew

McKBrew

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Sorry I do not have any insight for the location or a fan addition, but I was wondering if you could point me in the direction of the Gel Bottle solution?

Thanks,
I have heard from more than a few people that you should have the controller probe in something that doesn't react as widely to temperature swings (like ambient air). It makes sense. Even if the air temperature warms up in the kegerator by a couple of degrees, the liquid in the kegs is not going to react as quickly. By keeping the temp probe in a stable medium it should keep the kegerator from cycling on and off as much.

The gel from those cheap freezer ice bags (the kind that keep food cold in a lunchbox) is commonly used. Some people use an old white labs yeast vial and fill it up and then drill a hole in the top to put the probe through. I used a recycled prescription bottle.


Thank for the other responses. I think I'm going to install a small computer fan in there to circulate the air.
 

humann_brewing

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I have heard from more than a few people that you should have the controller probe in something that doesn't react as widely to temperature swings (like ambient air). It makes sense. Even if the air temperature warms up in the kegerator by a couple of degrees, the liquid in the kegs is not going to react as quickly. By keeping the temp probe in a stable medium it should keep the kegerator from cycling on and off as much.

The gel from those cheap freezer ice bags (the kind that keep food cold in a lunchbox) is commonly used. Some people use an old white labs yeast vial and fill it up and then drill a hole in the top to put the probe through. I used a recycled prescription bottle.


Thank for the other responses. I think I'm going to install a small computer fan in there to circulate the air.
Very nice, and the gel doesn't hurt the temperature probe as I thought you can't put them in water right?

The SWMBO just got a hole in one of those gel filled freezer bags, I hope she hasn't thrown in away yet I can just steal that one.
 

lombard

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I went down to Target and bought a little (3-4") 120v fan (I think it was a Hawaiin Breeze brand). Right now it's sitting on the compressor hump blowing up at my shanks. This is in a keezer with an 8" collar. When I add my fourth keg, I'll have to move the fan since the keg will be sitting on the hump along with my CO2 bottle.
 

juvinious

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I rigged up a blower with a radio shack 120V 4" fan in a project box:

It feeds air from the very bottom where it is the coldest into the tower and back out through the other side pretty strongly, cycling the air.
You could probably do the same and position the tubing to push the air around the collar area I suppose to cycle the air in your keezer.

Regarding the gell and probe I have mine sitting near my CO2 bottle (you can barely see it here, follow the thin copper wire down to that white blob):

Of course there still seems to be temperature differences from the bottom to the top.... If I add another fan I think it will be overkill since those things heat up allot, which will probably lessen my efficiency.
 

JesseRC

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I rigged up a blower with a radio shack 120V 4" fan in a project box:

It feeds air from the very bottom where it is the coldest into the tower and back out through the other side pretty strongly, cycling the air.
You could probably do the same and position the tubing to push the air around the collar area I suppose to cycle the air in your keezer.

Regarding the gell and probe I have mine sitting near my CO2 bottle (you can barely see it here, follow the thin copper wire down to that white blob):

Of course there still seems to be temperature differences from the bottom to the top.... If I add another fan I think it will be overkill since those things heat up allot, which will probably lessen my efficiency.
I've thought about doing the same thing, those perlicks warm up a bit sitting in 100deg weather.
 

pen25

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think of a ceiling fan. you want to pull the cool air up since cool air drops. so build a box that stands up off the bottom and allows air to enter. then use a fan with cell charger to blow the air up and then mount a tube to exaust about an inch from the top. you can put a cap on the tube and cut slots to allow the air to push outward. so if you mount the box in the center slot all 4 sides. if in a corner slot 3 sides. with will create enough air movement to allow the keezer to normalize more evenly. the problem is you will always have some variance.
 

SpanishCastleAle

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McKBrew (or anyone),
There is this recent thread on the controller probe in gel/water. The op in that thread might like some input from your side of the fence. Could you point me to where you found info that putting the controller probe in gel/water was a good thing?:)
 
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McKBrew

McKBrew

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McKBrew (or anyone),
There is this recent thread on the controller probe in gel/water. The op in that thread might like some input from your side of the fence. Could you point me to where you found info that putting the controller probe in gel/water was a good thing?:)
I'll have to see what I can find. I think most of what I read was in the kegerator build threads.
 

GilaMinumBeer

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I used to do the gel thing too. Cept' I wrapped my probe in a sandwich bag before immersing in the gel. I found the controller was cycling every 30 minutes with the bottle of gel on the hump. I am guessing that since heat rises......

Move the bottle and it stopped cycling as often but my fucets weren't staying very chilled. I used to get condensation on the faucet. After that. No more.

I have since opted to use a smallish styrofoam half cube. Shaped to the contour of a keg and taped against it. I still don;t get the condensation but the faucets are cold to the touch and the compressor doesn't cycle but a couple to a few times a day.

I have a spare 4" fan and wall-wort so, I may try that too.

I suppose another possibility is to get a secondary thermistor. With the Ranco the thermistors can be wired in series and teh Ranco will deduce an average from the probes. Thus, you could have one probe on the bottom and the other on the lid. Or just dangle one probe in the middle but, that ain't blingworthy is it?
 
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McKBrew

McKBrew

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I used to do the gel thing too. Cept' I wrapped my probe in a sandwich bag before immersing in the gel. I found the controller was cycling every 30 minutes with the bottle of gel on the hump. I am guessing that since heat rises......

Move the bottle and it stopped cycling as often but my fucets weren't staying very chilled. I used to get condensation on the faucet. After that. No more.

I have since opted to use a smallish styrofoam half cube. Shaped to the contour of a keg and taped against it. I still don;t get the condensation but the faucets are cold to the touch and the compressor doesn't cycle but a couple to a few times a day.

I have a spare 4" fan and wall-wort so, I may try that too.

I suppose another possibility is to get a secondary thermistor. With the Ranco the thermistors can be wired in series and teh Ranco will deduce an average from the probes. Thus, you could have one probe on the bottom and the other on the lid. Or just dangle one probe in the middle but, that ain't blingworthy is it?
If you have a minute later could you snap a pic of your styrofoam set-up?
 

GilaMinumBeer

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Sure.

It's nothing pretty.

I just chopped a corner off of an electronics (headrest DVD player) box insert and squashed it against a full corny and trimmed a bit. Poked a pencil though the top edge to make a hole for the thermistor and taped the lot to the side of a corny. I use my seltzer corny since it's the one that stays consistently full or is never taken out of the keezer unless I am re-filling (which I usually do with an auto-siphon rather than having to lift a full keg).

I find that with the open bottom edge it still gets a good read on the box temp but it stays close enough to the keg to be able to control compressor cycles. Having the top edge solid keep the warmer air from tripping the controller when the box is opened for service.
 

conpewter

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I don't use a chest freezer but I think you should just put the probe down at the bottom of the keezer. When you pull beer it is coming from the bottom of the keg (coldest), that will be the same temp your probe is that. That way you don't need to waste electricity with a fan (and the heat it generates) and the beer is at the temp you've selected.

The only issue there is the lines going up to the tap, but the large majority of the beer in a pint will be coming from the bottom of the keg.
 
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