Fridge cold, freezer not. Not no-frost system! (Liebherr 27210)

Hello,

I had some experience repairing both "no-frost" and "simple" fridge-freezers (I'm no professional, but have general knowledge and some tools).

If it is "no-frost" system, then checking fans, air valves, defrosting system is the way to go first.

If it is simple "top_fridge/bottom_freezer", all experience I had was simply fridge not cool enough, and freezer working OK.
This is due to evaporator lines going first through freezer section, and then in less dense manner going through fridge section. If there is a leakage, lack of refrigerant evaporates in freezer section first and only little evaporation happens in fridge section.

But what about the other way around? This does not look like lack of refrigerant?

In this fridge thermostat looks OK:
*if I set it on mid (3), fridge is ~+8degC, but freezer is ~+2degC;
*if I set it on max(7), fridge is ~+1degC, but freezer is ~0degC; Some food freezes inside fridge section.
*Condenser is clean and only slightly warm. System works on 40g of R600a.

Any suggestions on what to look first?

Looks like shortage of refrigerant, check for leaks.

But first, check the thermostat.

Bypass the stat and see how cold the cabinets get. That will tell you if it is charge related

Attachment 15080

Hello,

Thanks for suggestions! Just writing to update and to put thread as solved:

Changed the thermostat as found one spare, but this did only minor change - compressor worked for 6h non stop and freezer never gone below -3degC.
Reason was very small leakage on pipe going out of compressor.
Fixing this and re-charging r600a solved the issue - freezer now goes down below -20degC.

This might look obvious for experienced repair guys, but in my modest experience (~15 refrigerators repair) I have only encountered fridge-freezers with evaporation starting in freezer chamber and ending in fridge compartment - lack of refrigerant then makes lack of refrigeration effect in fridge, but not freezer. This Liebherr is other way around and this made lots of confusion to me.
Small lessons learned, maybe this will help to somebody else.

Thank you so much for the update and glad to see that you have solved the problem.