Fridge temp difference between top an bottom help

[Little owl1963]

Im finding that on number 5 , 2 degrees bottom and 8 degreees at top is this normal this is massive diffference !!!! ouside temp was 16 to 25 degrees .

But on another day 6 degrees at bottom and 8 degrees at top , outside temp was 6 degrees .

any research from your vehicles would be helpfull so i no what the normal difference between top and bottom should be ???

Also how often should the compressor cycle on and off ???
Been told every 20 mins ????

Hopefully welsh gas will read this ??

Thanks ian

 

[WelshGas]

Im finding that on number 5 , 2 degrees bottom and 8 degreees at top is this normal this is massive diffference !!!! ouside temp was 16 to 25 degrees .

But on another day 6 degrees at bottom and 8 degrees at top , outside temp was 6 degrees .

any research from your vehicles would be helpfull so i no what the normal difference between top and bottom should be ???

Also how often should the compressor cycle on and off ???
Been told every 20 mins ????

Hopefully welsh gas will read this ??

Thanks ian

There are a lot of variables involved ambient temperature, is the fridge side of the vehicle in sun or shade how often it is opened.
The cooling plate is on the rear wall so there will be a temperature difference between front and rear and because it is basically a box with a lid and cold air is denser than warm air there will be a temperature difference between top and bottom. This is because there is only cooling at one point the rear wall unlike domestic fridges or freezers that may have internal cooling as well as external cooling points.
The control system is fairly simple the Temperature level set will switch on the system which will function until the set temperature is reached and then switch off. The temperature will then rise slowly, a function of the insulation and outside temperature until the temperature range is exceeded and then switch the compressor back on.
The temperature sensor is behind a small grill R side about a 3rd down towards rear.
The temperature variation you observe is probably with and without the compressor running.
With an empty fridge you will get much more temperature variation than with a full fridge.
When packing alcohol against back wall , salad stuff top and near front and everything else in between.

 

[Little owl1963]

Many thanks , is the fridge in yours still a dometic ?? they say in T6.1 its a dometic .
do you no approx if the normal cycle of compressor kicking in then shutting off should be around 20 min time scales ?

 

[WelshGas]

Many thanks , is the fridge in yours still a dometic ?? they say in T6.1 its a dometic .
do you no approx if the normal cycle of compressor kicking in then shutting off should be around 20 min time scales ?

It's the same fridge.
How often the compressor is running depends on many factors . There is no set time interval. It may run for an hour or more when first switched on or for 10 minutes when the ambient temperature is low and the van cold. All I know it uses about 30% of the power an always On cool box does .

 

[Lambeth Cali]

Cool air falls. It’s probably the same in your fridge at home. What is the problem you’re having? Things freezing? Things going off?

We use ours for 17 day holidays and it works great. Never had anything go off. Worst we’ve had is things at the back freezing and of course water does start to accumulate at the bottom. I tend to have it on a low setting of 3 and we have one of these which helps stop things getting wet at the bottom.

SOSMAR Drainer with Drip Tray - 39 x 22.5cm Dish Drain Board Mat - Water Drip Tray Holder for Fridge Fruit Cup Mug Utensil Bathroom Accessories, Coffee Tea Trays https://www.amazon.co.uk/dp/B088LNNV9X?tag=eliteelect-21

 

[Roger Boeken]

Im finding that on number 5 , 2 degrees bottom and 8 degreees at top is this normal this is massive diffference !!!! ouside temp was 16 to 25 degrees .

But on another day 6 degrees at bottom and 8 degrees at top , outside temp was 6 degrees .

any research from your vehicles would be helpfull so i no what the normal difference between top and bottom should be ???

Also how often should the compressor cycle on and off ???
Been told every 20 mins ????

Hopefully welsh gas will read this ??

Thanks ian

You need temperature logger with Bluetooth wireless connection to your phone.
you will see a graph of temperature in time, allows easy readout compressor cycle (Is same as temperature. cycle). If you have 2 you can measure top and bottom or front and back of fridge at the same time, if you have 3 you can add outdoor or in vehicle temperature. You find some suitable devices for less than 20 euro on amazon. I dont recommend to.measure in empty fridge, will not give realistic image of fridge behaviour. What you measured look normal to me, hottest point at top as explained by others and lid is also thermal leak with less isolation. Goods against back wall can freeze because direct contact with heat exchange, therefor keep some air gap between food and back wall at all time.

 

[Emil Silenhag]

I use a 5-10 mm foam-sitting-pad (don’t know the English name for it) for outdoor activities. I put it up against the wall in the back of the fridge. Keep things from not freezing.
As said before, there are a lot of variables and factors affecting how often/long the fridge compressor is working, consuming amps. During winter camp here I Scandinavia I frequently se ambient temperatures around 20-30 below zero C-degrees. The fridge will not start the compressor at any time In fact we put things in the fridge to keep it from freezing

 

[andyinluton]

You need temperature logger with Bluetooth wireless connection to your phone.
you will see a graph of temperature in time, allows easy readout compressor cycle (Is same as temperature. cycle). If you have 2 you can measure top and bottom or front and back of fridge at the same time, if you have 3 you can add outdoor or in vehicle temperature. You find some suitable devices for less than 20 euro on amazon. I dont recommend to.measure in empty fridge, will not give realistic image of fridge behaviour. What you measured look normal to me, hottest point at top as explained by others and lid is also thermal leak with less isolation. Goods against back wall can freeze because direct contact with heat exchange, therefor keep some air gap between food and back wall at all time.

Or you could open your fridge & see if anything has frozen, if it has turn the temperature up a notch. Repeat until stuff doesn't freeze.
Make a note of the setting & re-use for as long as you keep the van.

Do it at home with some water bottles. not on the first day of your trip.

 

[Roger Boeken]

Or you could open your fridge & see if anything has frozen, if it has turn the temperature up a notch. Repeat until stuff doesn't freeze.
Make a note of the setting & re-use for as long as you keep the van.

Do it at home with some water bottles. not on the first day of your trip.

For some reason Littleowl 1963 insists on knowing the on/off cycle time of the fridge and temperature at different locations in fridge at different settings of controller. Normally I use setting 3 myself and sometimes 4.

 

[Little owl1963]

There are a lot of variables involved ambient temperature, is the fridge side of the vehicle in sun or shade how often it is opened.
The cooling plate is on the rear wall so there will be a temperature difference between front and rear and because it is basically a box with a lid and cold air is denser than warm air there will be a temperature difference between top and bottom. This is because there is only cooling at one point the rear wall unlike domestic fridges or freezers that may have internal cooling as well as external cooling points.
The control system is fairly simple the Temperature level set will switch on the system which will function until the set temperature is reached and then switch off. The temperature will then rise slowly, a function of the insulation and outside temperature until the temperature range is exceeded and then switch the compressor back on.
The temperature sensor is behind a small grill R side about a 3rd down towards rear.
The temperature variation you observe is probably with and without the compressor running.
With an empty fridge you will get much more temperature variation than with a full fridge.
When packing alcohol against back wall , salad stuff top and near front and everything else in between.

The temperature sensor you refer too , is this attached to the round black bottle thing which i presume is the compressor ???
or is it seperate from the compressor ? what does this sensor look like ? is it a wire with a copper probe on end it ? if a wire what colour ill try trace and find it , if i no what im looking for

 

[WelshGas]

The temperature sensor you refer too , is this attached to the round black bottle thing which i presume is the compressor ???
or is it seperate from the compressor ? what does this sensor look like ? is it a wire with a copper probe on end it ? if a wire what colour ill try trace and find it , if i no what im looking for

 

[Little owl1963]

Thanks , i m still researching temperatues right now got one temp gauge at base another top on basket , fridge empty , been on since this morning .
Appears to be on setting 2 . 5 degrees at bottom 10 degrees at top .
just put it up to setting 3 im trying get 5 degrees at top , cant get 5 degrees at top .

Is that normal 5 degree temp difference between top and bottom ???

On setting 3 , when first put up to 3 within 20 mins , bottom was zero degrees , top stayed at 10 degrees wonder why top did not also lower 5 degrees as bottom did ?
But strangley after 1 hour the bottom went from zero degrees to 5 degrees .???
Why when first put on went to zero degrees within 20 minutes , only to rise to 5 degrees after 1 hour .?? Should have kept it at 5 degrees what first went too . the compressor was silent on 5 degrees .
Still monitoring it at present .

To the left hand side of compressor there is an oblong control box wires going to it , seperate from compressor but next to it , wonder what that is ?

Just thought to check compressor / sensor working correctly if i open fridge lid within 5 mins would have thought compressor should start up , also if i switch up to number 4 same senario the compressor should kick in quickly to make it colder , what think these 2 tests ?
I will try later

 

[WelshGas]

Thanks , i m still researching temperatues right now got one temp gauge at base another top on basket , fridge empty , been on since this morning .
Appears to be on setting 2 . 5 degrees at bottom 10 degrees at top .
just put it up to setting 3 im trying get 5 degrees at top , cant get 5 degrees at top .

Is that normal 5 degree temp difference between top and bottom ???

On setting 3 , when first put up to 3 within 20 mins , bottom was zero degrees , top stayed at 10 degrees wonder why top did not also lower 5 degrees as bottom did ?
But strangley after 1 hour the bottom went from zero degrees to 5 degrees .???
Why when first put on went to zero degrees within 20 minutes , only to rise to 5 degrees after 1 hour .?? Should have kept it at 5 degrees what first went too . the compressor was silent on 5 degrees .
Still monitoring it at present .

To the left hand side of compressor there is an oblong control box wires going to it , seperate from compressor but next to it , wonder what that is ?

Just thought to check compressor / sensor working correctly if i open fridge lid within 5 mins would have thought compressor should start up , also if i switch up to number 4 same senario the compressor should kick in quickly to make it colder , what think these 2 tests ?
I will try later

The fridge is a top opening compressor fridge.
Hot air rises, Cold air sinks. The coldest part of the fridge will be at the base the warmest at the top.
if the fridge is on and you turn the Level from 2 to 3 or 4, making it colder then the fridge will cool the air on the rear wall and base to a lower temperature, BUT because you have the coldest air at the base convection air currents cannot form , you already have cold air at the base and warm air at the top.
The air at the top will only cool by conduction , and air is not a very good conductor of heat so it will take some time for the air at the top of the fridge to cool down.

When opening this type of fridge you do very little to change the internal temperature and so the compressor is used less thus conserving battery power.

A conventional fridge with a side opening door, as soon as you open the door all the cold air flows out of the fridge and is replaced by warmer ambient air and the compressor kicks in immediately thus using more power.

 

[Roger Boeken]

Thanks , i m still researching temperatues right now got one temp gauge at base another top on basket , fridge empty , been on since this morning .
Appears to be on setting 2 . 5 degrees at bottom 10 degrees at top .
just put it up to setting 3 im trying get 5 degrees at top , cant get 5 degrees at top .

Is that normal 5 degree temp difference between top and bottom ???

On setting 3 , when first put up to 3 within 20 mins , bottom was zero degrees , top stayed at 10 degrees wonder why top did not also lower 5 degrees as bottom did ?
But strangley after 1 hour the bottom went from zero degrees to 5 degrees .???
Why when first put on went to zero degrees within 20 minutes , only to rise to 5 degrees after 1 hour .?? Should have kept it at 5 degrees what first went too . the compressor was silent on 5 degrees .
Still monitoring it at present .

To the left hand side of compressor there is an oblong control box wires going to it , seperate from compressor but next to it , wonder what that is ?

Just thought to check compressor / sensor working correctly if i open fridge lid within 5 mins would have thought compressor should start up , also if i switch up to number 4 same senario the compressor should kick in quickly to make it colder , what think these 2 tests ?
I will try later

this is exactly why the control panel offers number settings for fridge and auxiliary heater and not temperatures: it is depending on many details different for any situation and is not meant to be accurate.
If you think the temperature of goods in fridge is too high choose a higher setting, Same for the parking heater: if the temperature is too low choose a higher setting.

 

[Little owl1963]

The fridge is a top opening compressor fridge.
Hot air rises, Cold air sinks. The coldest part of the fridge will be at the base the warmest at the top.
if the fridge is on and you turn the Level from 2 to 3 or 4, making it colder then the fridge will cool the air on the rear wall and base to a lower temperature, BUT because you have the coldest air at the base convection air currents cannot form , you already have cold air at the base and warm air at the top.
The air at the top will only cool by conduction , and air is not a very good conductor of heat so it will take some time for the air at the top of the fridge to cool down.

When opening this type of fridge you do very little to change the internal temperature and so the compressor is used less thus conserving battery power.

A conventional fridge with a side opening door, as soon as you open the door all the cold air flows out of the fridge and is replaced by warmer ambient air and the compressor kicks in immediately thus using more power.

your very knowledgeable man , that does shed some light on it .
So in a nutshell then when trying to determine the correct setting for the fridge at 5 degrees which it should be .
IM never going to get that same temp at both top and bottom .
So am i right in saying if you want fridge at correct setting you must go by the temp at the bottom , an put your temp gauge at bottom of fridge only ??
As it appears the top of fridge will always be around 5 degrees warmer .
So to summerise just go by the bottom temp only thats the best you can do .

Just turned it up to setting 4 now i let you no what reads in an hour or so , iv also put bottle water at bottom an another at the top see how goes .

So long as the bottom does not freeze anything should be ok .

One last question i no im a pain , but like get things as best i can .
Am i right in saying there will be temp difference at bottom of around 4 degrees , on same setting depending if the compressor is on or off ???

EXAMPLE compressor on zero degrees
Compressor off 5 degrees is this normal and correct operation of compressor

Thanks yet again

 

[WelshGas]

your very knowledgeable man , that does shed some light on it .
So in a nutshell then when trying to determine the correct setting for the fridge at 5 degrees which it should be .
IM never going to get that same temp at both top and bottom .
So am i right in saying if you want fridge at correct setting you must go by the temp at the bottom , an put your temp gauge at bottom of fridge only ??
As it appears the top of fridge will always be around 5 degrees warmer .
So to summerise just go by the bottom temp only thats the best you can do .

Just turned it up to setting 4 now i let you no what reads in an hour or so , iv also put bottle water at bottom an another at the top see how goes .

So long as the bottom does not freeze anything should be ok .

One last question i no im a pain , but like get things as best i can .
Am i right in saying there will be temp difference at bottom of around 4 degrees , on same setting depending if the compressor is on or off ???

EXAMPLE compressor on zero degrees
Compressor off 5 degrees is this normal and correct operation of compressor

Thanks yet again

After 2 or so hours there is normally a difference between bottom and top of about 5c, but there are so many variables that it cannot be written in stone. On Level 6 anything touching the back wall will definitely freeze.

 

[Little owl1963]

Fridge just turned off now , been on level 4 for 6 hours .
Final conclusion the top showed 6 degrees the bottom MINUS 5 degrees !!
overhaul variation of 11 degrees variation does seem alot , this test was with an empty fridge .

Just had bottle water at bottom an another in basket , neither froze prob take lot more hours to freeze water bottle at minus 5.

2 seperate fridge thermometers used both top and bottom .
Outside temp was 12 to 14 degrees .

Has any other california users had this 11 degree differance between top an bottom ???

Will do further tests with a full fridge , the next saga untill next time .

An lastly iv noted one owners suggests a 5 to 10 mm foam sleeping mat resting against rear of fridge to stop things from freezing should you so wish ??
Any comments on this .

A big thanks to all who have shared there advise on this , an a big thanks to welsh Gas , and a thumbs up .

 

[RockinNRollin]

We just use level 3; we found level 4 was freezing things and the stuff we keep in there isn’t too temperature sensitive - I stuck a Bluetooth thermometer in there and I think it averaged 8 degrees near the top on level 3.

 

[Little owl1963]

We just use level 3; we found level 4 was freezing things and the stuff we keep in there isn’t too temperature sensitive - I stuck a Bluetooth thermometer in there and I think it averaged 8 degrees near the top on level 3.

i would agree with that level 3 seems to be about right , what did you find the bottom temp was ??
Not heard of those bluetooth thermometers ?? tell me more , how much are they and were from ?
I presume they link to your phone or maybe control panel .
I also assume the 8 degrees was with full fridge ?

 

[Steve1]

Fridge just turned off now , been on level 4 for 6 hours .
Final conclusion the top showed 6 degrees the bottom MINUS 5 degrees !!
overhaul variation of 11 degrees variation does seem alot , this test was with an empty fridge .

Just had bottle water at bottom an another in basket , neither froze prob take lot more hours to freeze water bottle at minus 5.

2 seperate fridge thermometers used both top and bottom .
Outside temp was 12 to 14 degrees .

Has any other california users had this 11 degree differance between top an bottom ???

Will do further tests with a full fridge , the next saga untill next time .

An lastly iv noted one owners suggests a 5 to 10 mm foam sleeping mat resting against rear of fridge to stop things from freezing should you so wish ??
Any comments on this .

A big thanks to all who have shared there advise on this , an a big thanks to welsh Gas , and a thumbs up .

We go with meat at the bottom and more towards the back. Milk also at the bottom. Cheese and Salad and butter at the top in the basket and cans of drink because they don't like being as cold. Bluetooth thermometer central hanging from bottom of the basket thing. Set fridge to setting 5 which maintains about 2C to 6C in the centre. We have a small plastic grid to keep things from touching back wall. With this set up very occasionally our meat gets a layer of ice but doesn't properly freeze. And everything stays good like our fridge at home. I think once you get a decent amount in it the differential top to bottom gets a little bit less.

 

[NessL]

We have to look for the positives. If you hang an ice cube bag against the rear wall of the fridge, you can have ice for your drinks.

 

[RockinNRollin]

We have to look for the positives. If you hang an ice cube bag against the rear wall of the fridge, you can have ice for your drinks.

I like the lateral thinking here

 

[RockinNRollin]

i would agree with that level 3 seems to be about right , what did you find the bottom temp was ??
Not heard of those bluetooth thermometers ?? tell me more , how much are they and were from ?
I presume they link to your phone or maybe control panel .
I also assume the 8 degrees was with full fridge ?

This is what I have, got mine from Amazon (years ago) but doesn't seem to be on there anymore - not sure why.

Disc Mini Temp - Temperature Sensor and Logger – BlueMaestro

Bluetooth 4.3 Small size (33mm/1.30" x 9.5mm/0.37") Apps for iOS and Android API for custom development available Monitors temperature 9 - 12 months battery life Battery size CR2032 (replaceable) Logging storage 20,000 total data points (circular buffer) Range up to 150 feet (75 meters) FCC/CE...

bluemaestro.com

 

[Cali Phillip]

We go with meat at the bottom and more towards the back. Milk also at the bottom. Cheese and Salad and butter at the top in the basket and cans of drink because they don't like being as cold. Bluetooth thermometer central hanging from bottom of the basket thing. Set fridge to setting 5 which maintains about 2C to 6C in the centre. We have a small plastic grid to keep things from touching back wall. With this set up very occasionally our meat gets a layer of ice but doesn't properly freeze. And everything stays good like our fridge at home. I think once you get a decent amount in it the differential top to bottom gets a little bit less.

I do exactly the same in terms of where food goes, 5 seems to keep the basket centre average round 6c, but have seen 0 - 10 C on setting 5 !
Noted that if the rear of the fridge , (passenger side uk) is exposed to sun then the fridge temperature can drop to near zero still set on 5, I try to keep the passenger side out the sun where possible.
Given the wide variability and no internal air circulation for me 5 seems good given there's 200w of Rodgers solar on the roof so little shortage of power.
It's like the whole cali, a compromise.

 

[ThomasHJ]

i would agree with that level 3 seems to be about right , what did you find the bottom temp was ??
Not heard of those bluetooth thermometers ?? tell me more , how much are they and were from ?
I presume they link to your phone or maybe control panel .
I also assume the 8 degrees was with full fridge ?

Have you seen this thread yet? Myself and others have done some amateur testing, using a bluetooth thermomether. So there's some data and graphs to give you an idea. Not really scientific circumstances, but interesting none the less.

As @WelshGas mentions, there are a lot of variables that influence the fridge temperature. Outside temperature can play a huge role. When it get's real hot outside, a magnetic foil on the van where the fridge is, really helps. I actually did a DIY-version of this and it saved our fridge from switching off due to overheating last summer in Spain.



After my 'research' I decided to always try and keep the fridge on level 4 when there's real food in it that I do not want spoiled. I keep 'sensitive food' more to the lower back of the fridge. We do pre-cool the fridge before leaving home, if we get the chance. And I try and bring two small (500ml) frozen water bottles to put in the top front of the fridge. I can then use the ice in those to go into any cocktails I'd like to make ;-) We have also had two cans of coca cola explode in the fridge once while driving on the highway. I thought we had hit a large bird or something. ;-)