I sympathise with your problem B3. As they say, when you get older 3 things start to go - your waistline, your memory,......... can't remember the 3rd one.
....aaarrrgggh....fridges and thermostats....obviously a dark art that is only known by the initiated.
I have a fridge with a 1 to 5 thermostat. During the hot period (ambient temp at times was up to 29 to 30 degrees), I wasn't convinced that the fridge was working - or should I say cooling to a low enough temperature. Looking on't'web (the manual didn't say), the general advice seemed to be that the fridge at the warmest point (the top in my case) shouldn't be more than 8 degrees.
I have a fridge thermo and checked my fridge (which had been left on the mid point setting - about 2.5 - since installation) and the temp was way warmer. The thermo worked as by upping the number the temp dropped. But to achieve a <8 degree top shelf (5 degrees on mid shelf), I had to set the thermo to 4.7 (so not a lot of leeway left).
Since the heat wave, the fridge has remained on the same setting - ie 4.7 out of 5 and gives a rough <8 degrees top shelf, mid shelf 5 degrees - at an ambient temp of 20+ degrees.
I contacted the manufacturer - and after bouncing umpteen mails back and forth where I was asking for a chart (or something) that gave me the ambient temp, the thermostat setting and the achievable internal temp range - no one can tell me what temp ranges the fridge should achieve, given an ambient outside temperature of <25 degrees) at the different settings.
What I got again this morning was this:
'...As previously advised the temperature setting can vary due to the ambient temperature of the room.Â
The correct temperature is keeping the appliance cool and making sure the food is kept cool as the thermostat is set between 4.7 this wouldn't be a fault as the appliance is working correctly....'
I KNOW it depends on the ambient temp - I had been saying that to them (and I also know it depends on the fridge load) - but surely the thermostat must be calibrated to give a temperature range at a given setting under specific test conditions. IE I would have expected a reply of:
'... a medium load/empty fridge between an ambient temp of x-y, a mid shelf reading of n (+/- ? degrees) should be achieved at a setting of 1, blah (+/-...) at 2,...etc.
Otherwise how can you ever know if the thermostat is working 'correctly'? I love 'the correct temperature is keeping the appliance cool' comment. What does that mean exactly? That no matter what temp the thermo is giving, as long as it's cooler than the ambient temp, it's working ok?
I had a student who needed help with his English while doing a C&G refrigeration course. Not one of his teachers explained that the refrigeration system is designed to take heat out rather than put coldness in. Once I explained that to him, the lightbulb went on.
The thermostat setting should not be dependent on the ambient temperature so long as the ambient is within the specified working range of the fridge. The thermostat only knows about the temperature inside the fridge, it doesn't measure room ambient temperature.
If the room gets too hot then the fridge may not be able to provide enough cooling even if running full time. If the room gets too cold then the efficiency of the fridge falls and it will struggle to maintain the correct temperature.
I'm with you - I thought fridges were graded though to a class level code which then gave the working ambient temperature range? This fridge is SN-T according to the tech spec  - which gives - https://www.procoolmfg.com/refrigerator-climate-class-sn-n-st-t/
The manual though says:
'...This appliance has been designed to operate in ambient temperatures between +10 and +32 degrees C (50 and 90 degrees F)...'
BUT then says...
'...The interior temperature of your
refrigerator changes for the following reasons; • Seasonal temperatures,...
....
You may adjust the varying interior temperature using the thermostate. If the ambient temperature is higher than 32°C, switch the thermostate button to maximum position.'
The manual doesn't say what the thermostat setting is calibrated (roughly) to in way of temperature range.
The ambient temp may have been pushing the limit during the hot weather, although I don't think it hit 32.
I'm going to slowly reduce the thermostat setting down from 4.7, to see if it continues to achieve <8 (top shelf) and 5'ish (middle shelf) degrees at a lower number - but I can't see how that will work unless the thermostat or some other component is naff.
The thermostat setting should not be dependent on the ambient temperature so long as the ambient is within the specified working range of the fridge. The thermostat only knows about the temperature inside the fridge, it doesn't measure room ambient temperature.
If the room gets too hot then the fridge may not be able to provide enough cooling even if running full time. If the room gets too cold then the efficiency of the fridge falls and it will struggle to maintain the correct temperature.
Using your logic wouldn't that mean there would be no need for any method of adjusting the setting for the fridge? Or am I missing something?
I don't know what you're missing. The thermostat is the method for adjusting the setting for the fridge. I don't know why you can't just set an actual temperature rather than wondering what the 1-5 scale means - my freezer can do this so why not fridges too? Maybe new fridges now do this, ours is 25 years old now.
Some people like a fridge colder than others. I'm happy with a lower temp of just above freezing (at the coldest point) normally. A bit like have a thermo on a boiler. I'm happy at 19 in the winter, some people want 23...some...
The numbered thermos are still quite common. I thought the same as you - why on earth can't it just have a temperature setting instead? Maybe it leads people into falsely thinking that the whole compartment would be that temperature? Who knows...
I think at least that the docs should show the temp range that the fridge is capable of in test conditions - and what the temp diff roughly is between the coldest and warmest parts. Then a chart with the temp ranges mapped to the thermo settings.
Stupidly, the other fridge I have (part of a fridge-freezer) is coldest on the top shelf...why do that (and how?! Doesn't that take more energy moving the cold air up?)?
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Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
Not one of his teachers explained that the refrigeration system is designed to take heat out rather than put coldness in. Once I explained that to him, the lightbulb went on.
to operate in ambient temperatures
between +10 and +32 degrees C (50
and 90 degrees F)...'
refrigerator changes for the following
reasons;
• Seasonal temperatures,...
temperature using the thermostate. If
the ambient temperature is higher than
32°C, switch the thermostate button to
maximum position.'
Using your logic wouldn't that mean there would be no need for any method of adjusting the setting for the fridge? Or am I missing something?