ARB Fridge Testing

[wanderingjeep]

So, I had heard about ARB fridge temperature readings were off so I thought I would test it out myself.

I have a 50qt ARB Fridge. for testing purposes I put a large bag of rice and 4 cans of soda in the fridge as a buffer to slow temperature change as if I had actual food cargo. Here are the results of my test over 3 hours.

Ambient temperature of room is 78F.



What I am seeing is nearly 10 degree difference in cold area temperature from what the ARB fridge actually says it is. The temperature swings about 10 degrees as it warms and cools but will be affected greatly by how much stuff is in your fridge. My average temp difference was 10 degrees so to be safe, I could set my fridge to 25 degrees and be fairly certain that my food won't be all frozen. More testing to be done but I am satisfied with the results so far. :Wow1:

 

[cruiserpilot]

So the temp indicator is almost 10 deg off and you are happy? Try it over 3 days and see how it settles out.

 

[wanderingjeep]

Pretty common apparently. The Expedition Portal 3 year review says the same thing about the fridge. It most likely has to do with Thermocouple placement.

 

[tarditi]

I've found the same results anecdotally.
I can set my ARB50qt to 32 and drinks are "chilled" but certainly not frozen. I leave it set around 27 and everything stays nice and cold - nothing frozen at that setting though.

Overall, I'm quite pleased with the fridge - the temp difference is a known issue and easily accounted for, IMHO. Can always get a cheap cooler thermometer to verify.

 

[Ed B]

Same here, 27-29 seems be the best for my setup.

 

[philndz]

For those that don't already know, if you hold the +/- buttons simultaneously you can adjust the temp calibration. I went to a full +8 calibration and it seems a lot more accurate regarding the freezing point.

 

[wanderingjeep]

For those that don't already know, if you hold the +/- buttons simultaneously you can adjust the temp calibration. I went to a full +8 calibration and it seems a lot more accurate regarding the freezing point.

WOW!! Super great info!!! Can't wait to try it when I get home from work!!!

 

[RAFoutdoors]

I called ARB Customer service (in the Spring) and they walked me through the recalibration. They were great. It was very easy/quick. Readings seem to be much more accurate. I also adjusted a full 8 degrees.

 

[carbon60]

I called ARB Customer service (in the Spring) and they walked me through the recalibration. They were great. It was very easy/quick. Readings seem to be much more accurate. I also adjusted a full 8 degrees.

Mind summarizing the process?

A.

 

[wanderingjeep]

SUPER SOLVED!!!!!

So, I started playing with the recently discovered calibration process (thanks philndz!!!) It was really easy to get into calibration mode. I ran some of the same tests as I did as described at the top of this thread. Then I thought about air temperature vs the temperature of the items inside the fridge. With the air temperature changing upwards of 10 degrees over a period of an hour The right calibration could be calculated (or chased down anyway) but there is a better way. The reality is that the air temperature will change very rapidly but the contents being much denser than air would change temperature much slower. So, What I did was to take a bag of rice and bury my temperature sensor in the rice. This would measure the much slower temperature change of the rice which would give us a more accurate center temperature. With this new data I would be able to more accurately calibrate the fridge.

Okay so after a day of testing, I think I got it. I set my fridge temp to 31F and the sensor buried in rice is steady at 31 degrees. I turned the temperature up to 37F degrees and the rice temperature held steady at 37F.

Sometimes success can be so sweet. I started this thread to figure out what the magic number (offset) would be so I didn't freeze my food. This turned out way better! Now I can set it at the temperature I want my food to stay at. Thank you all involved.

 

[carbon60]

I will try that process when I return home, thanks for posting.

Why rice instead of water?

Also, note that, when the fridge is running hard to cool the contents, such as when you put something warm into it, it can freeze items that are touching the sides. (Despite the temperature being above freezing.)

 

[Big mike]

Fiddled around with my82qt the last couple days, and went to plus 8...almost spot on from freezing to just plain chill and it's spot on.
Mike

 

[wanderingjeep]

I will try that process when I return home, thanks for posting.

Why rice instead of water?


Also, note that, when the fridge is running hard to cool the contents, such as when you put something warm into it, it can freeze items that are touching the sides. (Despite the temperature being above freezing.)

I have an indoor/outdoor wireless sensor and while it is weatherproof, it is not waterproof. Theoretically the airspace between the rice would be Extremely close to the same temperature as the rice itself due to the proximity. I think water would work just fine.

 

[fireball]

Wow, great info. Mine is off by at least a few degrees but I never knew there was a calibration option. Very helpful!

 

[lysol]

Where in the ARB is your sensor? I would perform the test with it in the bottom, top, the top tray (definitely warmer there). I'm sure there is pretty significant change in the temp at the bottom compared to just below the lid.

Sent from a rotary phone.