Fridge Settings and Temperatures

[Wesel]

Ok, to make things worse, I did a second, totally not scientific test ;-) As said before, so many variables that can't be controlled, or I just don't feel like controlling, but still, I think very interesting results:

Some background info:

After my first test (sensor halfway down the front wall), I repeated the test with the sensor halfway down the back wall.

- Fridge set to 'Max'
- Started with fridge 'off'
- Outside max temperature at 23 (so much colder then in test1)
- Started with an empty fridge and later added food (most pre-cooled in home fridge)
- Van parked in the shade for the first 1/3 of the test.
- Van on leisure batteries, on hookup for 10 min. Then drove the van and then camped and had it on EHU.
- Opened the fridge several times while camping; normal use.

The most interesting thing is that I am seeing a minimum temperature of around -14c celcius. The second and most important thing is that I am seeing circa -12c constantly with no problems what so ever, while camping, thus using the fridge like you would in a real life camping situation. What surprises me the most is the huge difference between test1 (sensor halfway down the front wall) and test2 (sensor halfway down the back wall).

During test 1, on a hot day the sensor (front wall) measured 8c as the worst temperature with an empty fridge. So just above the 4-6c 'safe' temperature range.
During test 2, on a warm day, the sensor (back wall) measured -3c as the worst temperature with a filled fridge and was basically steady at -12 all the time.

That's a huge difference between front wall and back wall. And yes, the weather was different, but still.

For now I am concluding that there is a big difference between temperatures in the front of the fridge and in the back. Something that I had already noticed before starting testing. And, I do believe that the outside temperature (or better yet, the temperature inside the van) plays a big role as well.

Quite normal since we know that the cold is produced by the bottom of the rear panel.

 

[ThomasHJ]

True, but I would have thought the difference between the temperature in the back and in teh front would be smaller.

 

[thehorse]

@ThomasHJ The evapourator (the element that gets cold) is in the back wall of the fridge only, so if you measure directly on that side I would expect it to be very much colder than the front side that has no cooling element. Also if add lots of food, especially things that might insulate, like bags of salad etc. that may actually keep that wall even cooler, but the front side of the fridge would be much warmer.

 

[ThomasHJ]

@Wesel and @thehorse yes, you are of course both right. This is something I noticed before the tests, during normal use, but wanted to know for sure by testing. I think this is an important thing for people to know. Because if you set the fridge to max (or lower) stuff freezing might give you the idea the food is safe, while in rality the food in the front might spoil.

 

[thehorse]

Looks like they improved the software in the controller.

https://www.secop.com/fileadmin/user_upload/technical-literature/product-bulletins/electronics-controller/automotive_bd_electronic_unit_101n0650_update_03-2019_desn101e102.pdf

Mine has the older V1.01 software

 

[Frans_T5]

Dear Willwander, this is useful information, thank you so much for guiding me to this thread.
I have also be doing some measurements and found the following;
Start fridge box (our Cali shows deg. C at the control panel) 7 deg. C at 10.00h
Placed an 3L water plastic bottle (22 deg. C) in the fridge box
Placed an thermometer against the back wall (Tha's where the evaporator sits)
Placed an second thermometer close to the fridge box thermistor.
Removed the inspection panel donw in the left hand cabinet, three screws.
Placed an large 12V computer fan 4"x 4"
after 6 hours the fridge box compressor was still running, the rear panel temp -15,5 deg. C the ambient box temperature was 7,2 deg. C it had almost hit my selected temp, when I changed the 7 deg to 8 deg. the compressor stopped.
The ambient out door temperature was 21 deg.C
Honestly I started my checks because I had the feeling that our fridge box has lost cooling capacity!
The Dutch Cali importer advising to make a fan modification in order to get rid of the excessive heath at the compressor cavity.
I'll continue doing measurements because I still found the fridge box under preform.
I have a similar compressor fridge box, 39 l and this box cooling to -13 deg. C in about 2,5 hour. Beats me.

Last but not least... If I listen to my fridge box I can hear the flow of refrigerant expanding in the evaporator
But is is not a continuous flow it comes in waves with approx 4 sec interval.. does anyone have de same experience?
And yes I use spacers, one at the rear panel an one at the bottom. These I have purchase from our Cali service point. See attached photo, this is the bottom spacer, there is also an rear panel spacer.

Yours,
Frans...

 

[Frans_T5]

...
... So, if I had gone camping, I ought to have turned the fridge on at least 2.5 hours before placing food inside. ...

No. The empty fridge will not have accumulated enough cold. The air does not accumulate much cold.
What is fundamental is to place food which has already been cooled at home.
Empty recordings are not at all representative of what is actually happening.
[/QUOTE]

I usual trow a 3/4 filled plastic bottle with water in our frezer at home, this give the Cali fridge box a good start..

 

[thehorse]

Hi Frans,

Did you do any comparison how cold the back wall was getting with and without a fan?

 

[ThomasHJ]

I’ve loved following these posts really interesting, thank you all.
One thought, could you put your temperature gadget in your house kitchen fridge for a bit. I’d be really interested to see what it reads based on your usual fridge settings, just by way if comparison. I say this as I recently bought a cheap digital thermoter to put in the Cali fridge but first have had it in my the kitchen fridge. I was surprised how warm it suggest my fridge was on a middle shelf, yet all seems nice and cold and has always been on the same setting.

Tried it. Placed the same bluetooth thermometer I used for my experiments with the cali fridge, in the middle of my normal home fridge. The fridge is rather new, bought it last year, so it allows me to choose a temperature. It is set to 7 degrees C. The bluetooth monitor measured temperatures between 3 and 5 degrees. So, a few degrees colder then at which it is set. Hope this helps.

 

[Frans_T5]

Hi Frans,

Did you do any comparison how cold the back wall was getting with and without a fan?

Yes I did, the difference was -10°deg. no fan and -15,5° deg. With fan... so the difference is substantial.
I'm now preparing a modified panel, so I leave the original inspection panel as it is.
I have found a nice panel plate more or less the same material. I will fabricate a panel with a 12v fan and 3 position switch, OFF, half speed, full speed position.
My motto, I you don't try you never know.
So far my measurements show's significant improvement.

 

[Cali Phillip]

Yes I did, the difference was -10°deg. no fan and -15,5° deg. With fan... so the difference is substantial.
I'm now preparing a modified panel, so I leave the original inspection panel as it is.
I have found a nice panel plate more or less the same material. I will fabricate a panel with a 12v fan and 3 position switch, OFF, half speed, full speed position.
My motto, I you don't try you never know.
So far my measurements show's significant improvement.

Out of interest, is it worth trying a test with just the round inspection cover off, no fan ?
Thats the simplest change for most people to make

 

[Frans_T5]

Hi Philip,
It may give some difference but it will be far less. Warm air physically rise in that poor ventilated cavity.
I have leave the panel of for a longer period and noticed that the area still being very warm.
There is practically no draft .. I'm also in the process of figuring out.. fit the fan in suction or blowing.
When set in suction will mean all warm air cumulate in the storage cabinet. So I most likely go for blowing air in to the fridge box cavity forcing some kind of draft.
Sorry long answer but it isn't science.. but more try and error. I'll post some pictures about the progress.

yours,
Frans

 

[Calimili]

Too many chinese bluetooth gizmos for nerdy tests with no food in it. Just put some food and a few beers, put it on 5.
5 hours into the test drink a beer . Is it nice and cold? If yes the fridge is at the right setting for the ambient temperature. If the beer is not cold enough put a new can in and set the fridge to 6. Try again in 5 hours.
If the beer is too cold, than there is a user error as a beer can never be too cold. Repeat the test again starting with the fridge on 4.

 

[Frans_T5]

Too many chinese bluetooth gizmos for nerdy tests with no food in it. Just put some food and a few beers, put it on 5.
5 hours into the test drink a beer . Is it nice and cold? If yes the fridge is at the right setting for the ambient temperature. If the beer is not cold enough put a new can in and set the fridge to 6. Try again in 5 hours.
If the beer is too cold, than there is a user error as a beer can never be too cold. Repeat the test again starting with the fridge on 4.

, Many roads leading to Rome...

 

[Calimili]

, Many roads leading to Rome...

Do you have any pics of where you installed the fan?

 

[Frans_T5]

Soon, I just have found material to make the new panel, as soon I start my fabricating of the fan panel I'll publish pictures.
But honestly it is not rocket sciences, panel, 12V computer fan, look for a silence one.. low in dB's, small switch ..
Photo's will be published soon... for sure.

Frans..

 

[Frans_T5]

Soon, I just have found material to make the new panel, as soon I start my fabricating of the fan panel I'll publish pictures.
But honestly it is not rocket sciences, panel, 12V computer fan, look for a silence one.. low in dB's, small switch ..
Photo's will be published soon... for sure.

Frans..

When I made my measurements I had just removed the inspection panel and placed an 12V fan pointing towards the compressor and condenser, I powered the temporary fan with 12V from the cigarette lighter.

 

[sbmcd]

All very interesting and love the detail of the investigations, in our 6 years of Cali ownership which includes at least two months in Europe every year we have never had the fridge set above 4 in the hottest of weather's, normally setting 3 is used. This is our second fridge, first was replaced under warranty, both operated pretty much the same with settings.

 

[ThomasHJ]

On this forum most people recommend setting the fridge to '4'. Never had a reason to doubt that advice, although sometimes the fridge seemed 'not so cold' in the front part. But since my first test showed temperatures up to 8 degrees celcius in the front part of the fridge, I'm sticking with 'Max' for now untill I've had the chance to do some more testing. I guess that even though 8c is 'too high', it probably won't get you sick anytime soon. And this particular test was with an empty fridge. It's obvious that the back of the fridge, where the cooling element is, is not a problem. Will do a third test in real life camping situation soon. Will measure on the front wall again, this time with a filled fridge.

 

[Pd.]

I've followed your tread with interest, your results match pretty much with what I discovered and discussed in a tread earlier end of May/June.

My plan is to operate at 6 possibly 5 and see where it goes I've also brought a wireless Bluetooth monitor to replace the manual read thermometer that I previous;y used.

It is comforting to know that someone else is having the same concerns that I had other maintaining a fridge temperature and has reached similar conclusions. I'm also thinking of adding a freezer pack which will hopefully assist and can be 'charged' against the back wall.

The fan option looks interesting and look forward to the results.

Pd

 

[Benh76]

Removed the inspection panel donw in the left hand cabinet, three screws.
Placed an large 12V computer fan 4"x 4"
after 6 hours the fridge box compressor was still running, the rear panel temp -15,5 deg. C the ambient box temperature was 7,2 deg. C it had almost hit my selected temp, when I changed the 7 deg to 8 deg. the compressor stopped.
The ambient out door temperature was 21 deg.C
Honestly I started my checks because I had the feeling that our fridge box has lost cooling capacity!
The Dutch Cali importer advising to make a fan modification in order to get rid of the excessive heath at the compressor cavity.

Out of interest would there be any concerns with just leaving the inspection panel off to allow the heat generated by the fridge to escape ? I guess it's all about limiting heat absorption which works against the fridges cooling function ??

 

[WelshGas]

Personally I think people are over thinking this. There are so many variables involved. In practice, in Italy with temperatures of 35 to40c the fridge performed more than adequately on Level 5. Most fresh food was bought and consumed within 48 hrs, the only stuff that stayed in the fridge for longer was the Gin, Peroni, White wine and canned drinks and they were cold enough and in fact would freeze if against the back wall, which should be reserved for the C2H5OH.

 

[ThomasHJ]

I think you are probably right @WelshGas in the sense that we are overthinking this and about the fact that the back of the fridge should be reserved for alcohol ;-) I think some of us (me) just like to play with sensors and look at the data. But still, it nags me that in my first test on a hot day (but not as hot as it might get in spain or portugal, italy, etc) the temperature in the front of teh fridge got up to 8c. Because that is above the safe temperature to store food and we'll surely meet hotter days while away.

 

[WelshGas]

I think you are probably right @WelshGas in the sense that we are overthinking this and about the fact that the back of the fridge should be reserved for alcohol ;-) I think some of us (me) just like to play with sensors and look at the data. But still, it nags me that in my first test on a hot day (but not as hot as it might get in spain or portugal, italy, etc) the temperature in the front of teh fridge got up to 8c. Because that is above the safe temperature to store food and we'll surely meet hotter days while away.

My question is, how long and what food are you storing in the fridge? We rarely have any food in the fridge for more than 48 hrs and frequently less than 36 hrs. Salad stuff in the front maybe, alcohol in the back and milk , cooked meats etc: in the middle.

 

[ThomasHJ]

When on holidays we often keep 3 days worth of food in the fridge. So 3 evening meals. Meats for the BBQ, etc. Things like chicken and fish you really don't want to keep at higher temperatures then 4-6.