Keezer temp cycles

[TommyTbar]

So I have read the suggestions on this topic but still can't get my keezer to have a good cycle rate.

I have a 5cu ge freezer with a 8x10 collar that is insulated with 3/4 inch reflective board. Controlled by a Johnson digital temp controller, set to 38 degrees with a differential of 4 degrees, I have the probe taped to the side of a full keg with some paper towel in between the tape and probe, almost at the bottom of the keg. There is currently two other kegs that are half full in as well, so enough thermal mass. And have thrown a light inside and turned off the lights in the room to check for leaks.

It is turning on every 17 -25 mins and cycling for about 6-8 mins. This seems like alot i comparison to what I've read.

I don't have a fan yet but don't really see that helping a whole lot other than keeping the lines a bit cooler at the top.

Any tips or advice would be appreciated





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[Dolomieu]

My first two thoughts are:
Add a fan
Better insulate your probe

 

[Indian_villager]

Put the probe in a half gallon of star san.

 

[SouthernYankee]

I'm using a GE 7.0 freezer and don't have any problems using a Ranco temp. control.
Several things I did.
I added the probe into an old White Labs tube by drilling a hole in the cap and then sealing the temp probe inside the tube with silicone caulk.
Also I sealed around my reflective board...top, bottom and sides with the caulk. Makes a great seal. I didn't notice any around yours?
Also added the fan with pvc tubing which lifted the kegs off the floor 2".

Hope this helps a little.

 

[kwadric]

With a four degree delta on your temp controller cycling that fast has to mean you are measuring air temp more than the liquid temp in your keg.

I have a similar set up to what you mentioned except that I have the probe coveted reflex bubble insulation and bungee corded to a corny full of water. My temp controller is set at 42f w a delta of 2f. It runs at about a 15% duty cycle (about 18 min on and 100min off).

Stuck a thermometer in the keg and see if the temp matches what your controller says. This might help give you an idea if you are measuring air temp (assuming the probe and thermometer are close).

 

[acidrain]

Move the probe up to the middle of the keg. Use more insulation over the probe.
Get a fan.

 

[TommyTbar]

So I insulated the probe with some stuff leftover from the build and just went 65 mins with a 6 min cycle, so 10% duty cycle, I'll have to get a fan in there soon but that seemed to help drastically, thanks for the help guys, Southernyankee I like the seal in between your insulation, might have to try that, also that fan set up is sweet, I don't really have the room for that in a 5cu haha


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[SouthernYankee]

Glad to help.
Seal all you can!
If you think about it...even with the insulation reflective board. Cold air is still going between the board and the pine wood. The silicone helps in sealing the cold air from going between the two. Thus keeping the cold air in the freezer itself and not between the insulation board which defeats the purpose.

 

[day_trippr]

Paper towel is essentially a no-op in this use.

Next time you buy something that has closed cell foam packaging, save the foam. With a 4x6 by one inch thick slab of foam trapping my temperature probes against carboy or keg the tracking is excellent (meaning the ambient temperature isolation is very good) and you take full advantage of the hysteresis provided by that huge thermal mass in the vessel. My keezer is currently cycling on a 3.5 hour period with a 20 minute run, with 1.5°F differential setting...

Cheers!