Having problems with keezer temps..need advice

[BrewinSoldier]

Hey guys and gals! I built a new keezer specifically so I could have more capacity for kegs. I bought a brand new whirlpool 15 cu ft chest freezer and built it into a coffin keezer. I even fabricated a custom tower for it which I'm having cooling problems with as well. I need to play around with some other options on the tower before I get any further. The beer coming out of the taps is just too damn warm, but it could be because of the other issue I'm having with the keezer.

One issue I'm having is the dang water pooling. I never had this in the 7cu ft keezer I built with a collar.

I am getting an excessive amount of water pooling on the bottom of the keezer. I vacuum it up and the next day it's back. I put some of the foam insulation around the bottom keezer size in case there were any leaks coming out. The water today wasn't as bad but still there.

Here is the weird part. I have my controller set to 37°. I have the temp probe submersed in a jar of water on the keezer hump inside. I tested the water temp against the probe with two different thermapens and it's reading accurate. Problem is the beer temp in the keg is way high higher...like 42°. I don't get this??? And that's running straight from the keg a ball lock liquid fitting with a tap attached straight to it, so no beer lines to go through, etc. And I left the taps inside the keezer over night so they would be chilled.

Any advice would be greatly appreciated. I'm going crazy over here.

 

[BrewinSoldier]

One other thing I should mention, I already had the small fan in the upper left corner sitting in the keg. That one was there to try and recirculate the air in the keezer. I didn't think it was big enough so I ordered the big brother one and mounted it about 3" from the inside top lid, facing down so it's blowing downwards and hopefully circulating the air around. I just installed that and now the temp probe in the water is reading 43°. Hopefully when it gets back to 37° the actual beer in the kegs will be the same.

 

[mongoose33]

Is there insulation inside the tower?

Condensation of this magnitude would generally be a sign that there's an air leak somewhere; you're bringing in moist, outside air and it's cooling and condensing.

Are you sure your lid seals tightly to the freezer mouth? Looks to me from the picture that you have some sort of weatherseal on the mouth of the keezer. I suspect that doesn't seal as tightly against the lid seal as you might think it is.

I've built a couple keezers; both times I had the lid seal against the wood collar, and adjusted it with the screws until it sat square.

 

[BrewinSoldier]

Yeah so the way I made the tower, 3 lines run in one side and two run in through the other side. Inside of the tower is 1.25" copper tubing from one side of the tower to the other, both going back into the keezer. There is a 1.25" copper tee at each tap where the line comes out and into the shank. The around all the copper tubing is the foam pipe insulation and at every tee in the tower going to the tap. I'm thinking I'm not getting enough cold air through the tower so I'm actually considering taking out the copper and just running the lines through the black foam insulation. It should leave more room for the air to flow through. Either that or the tower fan I have isn't powerful enough.

 

[kh54s10]

How long did you have the keg in there before you took the temperature. If it was room temperature it may take a couple days to equalize.

 

[BrewinSoldier]

The kegs have been in there for about 2 weeks. Now that I've added that new fan, it sure is taking a while to get back to 37°. It used to get there really quick before I added that fan today. Once it get them to 37° and stabilizes, I'll pour from the kegs again and check temp. If they are at 37°, then I can start working on my tower temp differential, which after the first pint pour, is about 4-5 degrees. The first pint is coming out way too warm for my liking and I don't want to be wasting a pint of beer everytime I pour.

 

[Sparkncode]

Im not sure i would put the temperature probe in water as the thermal mass can make it turn off too often or for too long. You need the air in the keezer at your target temperature not a jar of water. Thr air could warm up well before the water changes temperature when the keezer goes off
Especially when trying to cool down. Taping it to the keg will help with cooldown but could overcool other items on thd keezer

 

[mongoose33]

Im not sure i would put the temperature probe in water as the thermal mass can make it turn off too often or for too long. You need the air in the keezer at your target temperature not a jar of water. Thr air could warm up well before the water changes temperature when the keezer goes off
Especially when trying to cool down. Taping it to the keg will help with cooldown but could overcool other items on thd keezer

I'm going to have to disagree with this. If you tape it to a keg, you'd better be sure you have it taped where there is beer on the other side of the keg wall, otherwise, you'll have issues.

I have mine terminating in a canning jar with about a pint of fluid in it. This gives me a much slower response than if it were responding to air temps. Terminating it in liquid is analogous to terminating it in the beer itself, and it will maintain beer temps more consistently.

Further, different kegs are likely to have different amounts. A full keg has a lot of thermal mass to buffer temp changes, a nearly empty one not so much. By keeping my probe in a consistent vessel, my overall temps are more consistent.

 

[Sparkncode]

The only reason i have put it on a full keg was being in a hurry to cool but as you say issues if there is no beer and it can cause beer line freezing so only an emergency measure to get a keg cool.

I normally use air temperature at the top of my kegerator. The STC1000 and my fridges delays prevent fast cycling and it works well. Sensing at the top ensures all air is arround target temp. If the air is right they everything will acliametise eventually provided there is a bit of air stiring going on

 

[TechFanMD]

The size of that tower, and being outdoors and made of steel is going to transfer a lot of heat....with air temp of 37F I don't see you being able to get enough airflow through that to keep those lines cold.

How about running copper through it and pumping glycol through the copper? All of the lines and the glycol line inside of the foam insulation.

 

[TechFanMD]

I'm going to have to disagree with this. If you tape it to a keg, you'd better be sure you have it taped where there is beer on the other side of the keg wall, otherwise, you'll have issues.

I have mine terminating in a canning jar with about a pint of fluid in it. This gives me a much slower response than if it were responding to air temps. Terminating it in liquid is analogous to terminating it in the beer itself, and it will maintain beer temps more consistently.

Further, different kegs are likely to have different amounts. A full keg has a lot of thermal mass to buffer temp changes, a nearly empty one not so much. By keeping my probe in a consistent vessel, my overall temps are more consistent.

If it is measuring air temp, it will keep the air temperature fairly constant - why would it matter if one keg had 5 gallons and the other 1 gallon - if the air around them is held pretty constant it shouldn't freeze one or another (especially with a fan for airflow)? If you measure in a jar of liquid, the air temp may go from 37F to 42F before the water warms enough to turn on cooling. Then it may run until the air temp is actually 32F before the water cools to 37F and turns it back off again. In that time the emptier keg may actually have a degree or two of swing.

I'm not sure why measuring the air is a bad idea since it would be held at a constant temp and limit large swings completely.

Also, with the submerged method, the air warms and expands more, then cools and contracts thereby creating a slight vacuum and drawing in outside air...and moisture. With the probe in air, the compressor would cycle more often but keep the interior at a more consistent temp and reduce condensation.

For curiosity I went to see if someone has measured this -and of course someone did. http://www.homebrewfinds.com/2014/10/temperature-probe-place-to-immerse-or-not-to-immerse.html

 

[mongoose33]

If you want your keezer cycling on and off a lot, measure the air temp. If you want to limit cycling, measure the liquid.

 

[day_trippr]

^exactly^

This is a plot from a six channel keezer monitoring app I cobbled together years ago. The key should explanify it all.

The point is the keezer is controlled by the keg temperature, and you can clearly see the "On" and "Off" points (I have a 2°F differential programmed into the controller) in the Keg trace. Meanwhile you can also see the comparatively pronounced air temperature swings - the air temperature crosses the keg temperature quite quickly with compressor state changes.

That's a 24 hour plot, and the compressor cycled four times over that period. If I ran the keezer from the air temperature it would cycle close to four times more often...

Cheers!

 

[SanPancho]

Keep the probe in water. But put something under the water to insulate it. The kegs have rubber bottoms, which insulate. The water is touching the cooler walls and getting direct heat trnsfer. It gets cold well before the kegs do. Break the direct contact of water/probe to metal.

Seal that sucker up to stop the condensation.

fan is a heat source, bigger isnt necessarily better. Insulate the water bath, seal the air gaps and i bet a smaller one does the job just fine.

Personally id lose the tower. Thats just me.

 

[Jag75]

You have to have good air flow in that tower. If there is too much shoved in the air wont move . My tower has a foam insulation and the beer lines only . I have a hose coming off the fan housing going up into the tower. Like the other poster stated if that keezer is outside it will struggle in warm weather . The room where my kegerator is located has no ac. During the summer it struggled to keep a temp of 40. I had it set to 38*. I put in a portable ac and it helped big time . One thing I noticed is your tower has a lot of space . I would say more cubic inches then most so its gonna be harder to keep that area cold. I must say that I really like your set up . It looks awesome .