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Hello,
I am looking for help please on the cause of temperature instability on my Liebherr Larder fridge Service number 0969722.00, until recently the appliance has proved perfectly reliable over more than 20 years, it has never needed a service visit or fault fixed until now.
The issue is that the fridge temperature measured carefully on middle shelf using a calibrated fridge/freezer thermometer swings quite widely over some hours between 2degC and 10degC on setting 5, there are long periods where the compressor is not heard to be running and so the cabinet is not keeping food at or near 3-4degC which is what I want. Over the past few months I have had to increase the temp dial setting from No.4 where it always was for years up to No.5 or 6 and even then the cooling is inconsistent with far too much swing in the Min-Max temps.If I set the thermostat dial to Max which is No.7 the fridge gets very cold even down to 0.5degC and is better for the food but too cold and too close to freezing and I should not be running the fridge on Max in the winter months. Before I contact Liebherr Service would someone have a think about whether my issue is probably caused by the thermostat alone or could it be something else, is the thermistor and sensor part of the thermostat and that coil tube? Is there something wrong with a sensor on a circuit board?
Does the fact that the fridge can go down to 0.5deg C on Max indicate the compressor, the gas and the cooling parts behind the fridge cabinet maybe OK or is that a false hope? I cannot see the back of the fridge just yet until it gets pulled out of its cabinet housing, but I do not think there is an issue with dust blocking the grids etc. I am not inclined to consider replacing the fridge as it is such a good appliance and the furniture cabinet was made for the fridge, I do hope that it should be possible to fix the problem.
I look forward to some responses from fridge experts please. Any questions please ask.
Thank you.
Peter.“The issue is that the fridge temperature measured carefully on middle shelf using a calibrated fridge/freezer thermometer swings quite widely over some hours between 2degC and 10degC on setting 5, there are long periods where the compressor is not heard to be running and so the cabinet is not keeping food at or near 3-4degC _uhh! if the compressor does not run for long periods it`ll get warmer not colder – which is what I want” Most likely the thermostat is duff and has lost part of its liquid in its coil rather than the usual fridge runs forever fault or the doesn`t run at all fault. Bit of a guess since the Liebherr parts site does not recognize your model nor the service number because it does ask for the serial number which you do not give.
Things to check: the ice line relative to the end of the thermostat end of coil “sensor” placement. for example if the iceline ends before the sensor you`ve lost pipe work refrigerant or and a weak compressor.
Does this thing have a fan cooling motor for the condenser? If so does that run?
Printed circuit board……has it really got one?
“If I set the thermostat dial to Max which is No.7 the fridge gets very cold even down to 0.5degC and is better for the food” Could be the t/stat is ok if the unit actually switches off rather than running forever, but the iceline could still be at fault instead.
Did find some t/stats on the Partmaster site where you are very well warned to tread carefully. The Liebherr stat as a Liebherr part is priced at £126.90, an alternative is the Hotpoint version at a gob smacking £384.08 (someone has got a poor sense of humour!) and a Danfoss stat at £47.09 and there maybe others. Take these stat price examples with a pinch of salt as all these examples were just based on a Liebherr Ki1840-22 (one of many with a -?? presume versions) the 0969722.00 means nothing to the site.Thank you Andy, the serial number on the plate is 18.221.482.0 and yes I too found it hard to get that model recognised in any parts lookup. I only said I wanted the fridge to hold the temp at 3-4degC which is normal I believe, I do not mean I want to have the compressor off for long periods, it should only be off for as long as the temp holds at the setting within its tolerance range. There is no fan for the compressor/condenser and probably no circuit board either as the fridge may be old school with just the thermostat switching the compressor on and off rather than being controlled by other electrical components but I do not know. When the fridge worked normally at setting No.4 or 5 the motor would kick in and be on and off periodically as you would expect, open the door for too long and that would quickly bring the motor in. Now, you can open the door and the temp rises but no action from the motor until the temp gets past 9 or 10degC and then it kicks in and brings the temp down again but that amount of swing is not right is it? I think I understand what you mean about the iceline, is that the chilled refridgerant and the sensor is picking that up in that position behind the frost plate on the back wall? is that the bulb on the end of the thermostat coil?
Forgot to say that I find the whole business of fridge thermostats ridiculously difficult to fathom, many so called compatible types at very different prices, Ranco, Danfoss and others, did Liebherr use Ranco as OEM, not sure, maybe I can see the make and model when looking into the exposed control knob housing.
Hi,
Your KI 1840 index 22-147 is now 23 years old and unfortunately the thermostat part number 6151086 is no longer available with Liebherr.
It is listed as either a Ranco K59-L1287 or a K59-H1300 both versions were used on this model.
It may be worth searching the internet if someone has old stock of one.
It must be noted the thermostats have a constant cut in temperature of +3 degrees regardless of cut out setting ie coldest (7) or warmest (1) on dial and the capillary measures 900.
So you cannot just fit any type of auto defrost fridge thermostat as these generally have a much higher cut in temperature, and will not improve your problem.
Tony.Thank you Tony, I was told that either this 53LR05 Compatible Fridge And Fridge Freezer Thermostat (ukwhitegoods.co.uk) or this would be correct 6151087 Fridge Thermostat (ukwhitegoods.co.uk) but are you thinking that it is probably the thermostat, just checked the thermometer again and the temp has come down to 4degC but it was over 9degC earlier.
I can not confirm the thermostat is your problem without being there to check the thermostat cut in and cut out values, the thermostat 6151087 has a much lower cut out temperature compared to your original and has a higher cut in temperature after defrost but has the same capilary length.
Original cut out on maximum is -23c and -8c on warmest and a constant cut in temperature of 3.5c plus or minus 1.1 degree.
The 6151087 cuts out on maximum at -29c and -18 on warmest with a constant cut in of 5 degrees plus or minus 1.1 to 2c.
I would not advise fitting a 6151087 as you will probably have food freezing in the fridge.Thank you Tony, you do know your stuff that is clear. May I just ask, what would you expect the Min-Max temps to be on this fridge on setting 5 say, overnight I recorded a Max of 9degC and a Min of 1.5 degC Fridge now sitting at about 7-8degC which is not cold enough. Compressor sounds much the same as it always did, gently humming when on. Stat 6151086 appears to be available here, is this it? LIEBHERR MIELE GENUINE RANCO FRIDGE THERMOSTAT 04LR 6151086 | eBay but those cut in cut out figures for a 6151086 stat you mentioned are not the same as this stat on Ebay states, so its confusing.
Temperatures:
from cold: -19.0 ° C
hot from: -7.0 ° C
a constant: +5.0 °
As a matter of interest my capillary tube that goes down to and behind the frost plate is white coloured not all silver. I don’t suppose you are working in the South Hertfordshire area or know someone who is? Finally Tony, I am beginning to wonder if my problem is more to do with the compressor strength or gas etc rather than the stat but I just cannot be sure without someone coming out to see it. Clearly on Max setting 7 the fridge will come down to very cold but on the other settings 4,5,6 it is not correct as I cannot obtain a 3-4degC average temp.Update on my fridge cooling issue Tony. I reset the Max Min settings on the thermometer at 10am this morning, since then the Min has gone down to 0degC and the Max up to 8degC, currently the actual temp is about 6degC on lowest shelf. Is this really normal, maybe I am just not aware of what normal looks like? but a swing of 8deg is a lot in my view. If the fridge can get down to 0degC on setting 5 then maybe the compressor is OK after all and it is pointing to the thermostat. Liebherr have advised me that the original part was in fact Thermostat Ranco RC K 59-L 1287/000. Peter.
Hi Peter,
Firstly I had another Engineer in Somerset try and purchase an obselete thermostat from this company in Brighton without success, no response to emails and not anwsering phone calls, so dont hold your breath on being able to get the 6151086 as I have preiously advised is a Ranco K59-L1287, I have full access to the technical specifications etc on all Liebherr parts etc as a service agent for them for over 23 years.
With this I can confirm my earlier statement on cut out and cut in temperatures that Liebherr require from the thermostats they fit to individual cabinets.
I can only assume your fridge does not have any compressor or refrigerant issues if at certain times it is reaching temperature, the thermostat will stop the compressor relative to the setting at the required temperature as measured at the end of the capillary tube fastened to the rear wall of the fridge eaporator, The rear wall will go through it’s defrosting period untill the temperature at the capillary end reaches 3.5 degrees plus or minus 1.1 degree.
Room ambient temperature will play a part in how long the fridge remains in defrost until the cut in temperature can be achived, Cold rooms means it will be off longer and can cause higher interior temperatures in the fridge.
You can lower the cut out temperature on your dial, but the cut in remains the same and cannot be adjusted from it’s preset temperature of 3.5c + – 1.1c, which should then give you an average temperature in the fridge of around 5c but this varies from the bottom shelf to the top shelf.
Tony.This on eBay perhaps – https://www.ebay.co.uk/itm/256302851741
Well done turbafan, that was the other version listed in my previous post that Liebherr also used, the end code is 003 and not 001 but this could just be a production date code.
Ok folks, then the question needs to be asked, is it normal for a fridge, this fridge, to cycle between approx 0.5degC up to approx 8.5degC and then down again repeatedly? I would have thought in the winter months I would not need to run as high as setting 5 with not much now on the shelves.
Hi there, so would it be safe to assume then that the thermostat listed here Genuine LIEBHERR Fridge Freezer Thermostat Refrigerator Sensor K59-H1300-003 | eBay being the same part as the Miele listing that Turbofan found, is technically identical to K59-L1287/000 both being badged as part no. 6151086.
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