Newest Threads

acefaser · 06-27-2011, 08:34 PM

Just wanted to say thanks again for this info.
I have fine tuned my temp and it is holding great now. I wanted to change the temp a few degrees and tried with the large dial knob that lets you fine tune it when the freezer is operating normally, however I got large temp swings and couldn't get the temp I wanted. I then tried adjusting the temp by only turning the course adjust screw you mentioned and can set the temp perfectly. So if anyone else is having problems don't touch the large dial and only use the course adjust screw. My screw works out to be about 2 degrees warmer for every one full turn clockwise (screw in).

kenc_zymurgy · 06-27-2011, 08:57 PM

Quote:

Originally Posted by ryclo

My freezer is swinging widely, 30's to 50's... I ended up going back to my controller to keep it tighter.. It could be because its in my hot garage?

Quote:

Originally Posted by carrotmalt

I'd be interested in what kinds of temp swings this translates into for the beer itself. I suppose it might be different for one gallon vs. five, but were these readings with a probe suspended in the air?
Also, have you taken readings the same way with while using your external controller t-stat to see what kind if swings it shows?

Agreed - you need to be reading some average temperatures, not the air temperature. Tape the probe to the fermentor, or stick it in a small glass of water. Oh, is there anything in the freezer? You need some mass in there to get the temps to average out.

Think about the A/C in your house. Your thermostat may be set to 76F +/-1F, but the air out of the vents is ~ 60F. That's normal, not a problem at all. It's not a 17F swing - the 'stuff' in the room will be 76F +/-1F.

Since a fridge is small, and normally packed with a lot of 'stuff' and little air (compared to a house), the air will normally be much colder than the 'stuff' during a cooling cycle - it has to to overcome the mass of all that 'stuff'.

-kenc

**emjay** · 06-27-2011, 09:12 PM

Well yeah, the compressor only turns on or off, producing very cold air until the desired temperature is reached, then turning off. It's not capable of adjusting how much it cools the air by... temperatures are maintained strictly by how long the compressor cycles on and off for.

Because of this, I have a tiny bit of ice on my freezer walls at times, despite being set to 70° right now - but the beer itself (according to the thermostat with the probe attached to it) remains at a very stable temperature.

ryclo · 06-27-2011, 10:01 PM

I have a datalogging RTD thermometer that I will stick into a 3 gal keg of water and see what kind of fluctuations I get this weekend! That will tell the tale!

GnomeEnthusiast · 06-28-2011, 11:17 AM

Quote:

Originally Posted by ryclo

My freezer is swinging widely, 30's to 50's... I ended up going back to my controller to keep it tighter.. It could be because its in my hot garage?

Same here. And now the controller is used for the fan as well, so that's not running 24/7.

wizodd · 06-28-2011, 07:36 PM

Temperature swings?

Two words.

Thermal Mass.

As has been noted, refrigeration equipment basically runs at one speed--high.

The chest I converted to a fridge has something over 100# of water in bottles at the bottom (you never see stuff at the bottom of a 35" deep box...) All refrigeration equipment keeps a more eve temperature with more mass and more insulation.

I currently am monitoring the unit with 2 external alarms, the external controller and the thermometers inside the box. All reading air temperature.

Seldom do all of them match, but the external is set to keep a 33-37 degree range, which it does well. The other thermometers range from 32 to 40 depending upon their location.

An internal circulation fan would probably even things out, but the swings I'm getting are fine, stuff that needs to be colder goes near the bottom, stuff that shouldn't freeze on top.

Now that I have about a week of data, I'll move a couple of the sensors into bottles of water, here I expect the swings will be far less.

OHIOSTEVE · 07-03-2011, 08:36 PM

Quote:

Originally Posted by HansF

I just picked up (free) an older Amana chest freezer. Not sure of the year, but here is some info:

It's got to be 10-15 cf as I can easily fit 6 corny kegs, 5lb CO2 tank and probably a 30 pack inside. Cleaned it up and plugged it in and it works great. I dug into the thermostat hoping to find a coarse adjustment screw and found this:

There are tiny screws inside the "cut in" and "cut out" holes. I assume if I turn those counterclockwise, it will run warmer? Turn both the same amount? Some insight would be helpful.

I just picked up an old amana... havent tore into it yet but wanted to know if you had made any headway with this one?

HansF · 07-04-2011, 07:12 PM

Quote:

Originally Posted by OHIOSTEVE

I just picked up an old amana... havent tore into it yet but wanted to know if you had made any headway with this one?

No, I have just about given up on it.

OHIOSTEVE · 07-04-2011, 07:24 PM

Quote:

Originally Posted by HansF

No, I have just about given up on it.

Mine absolutely has no screw. so a mini digital controller will have to be bought. Took it apart today, and there is nothing.

RevFry · 07-04-2011, 10:30 PM

Quote:

Originally Posted by OHIOSTEVE

Mine absolutely has no screw. so a mini digital controller will have to be bought. Took it apart today, and there is nothing.

I have the same "cut in" "cut out" on my Whirlpool EHH-180F.

I have a diagram inside the service plate. I'll add a photo of it in a moment.