Liebherr Fridge Started Freezing

[jlovick]

Hi, looking for some suggestions as to why my 2 year old Liebherr fridge might have started freezing food. It is model Liebherr K4260 185cm larder fridge (no freezer).
Just recently it has started to freeze things. The thermostat on the front says 5 degrees but the compressor sounds like it is constantly running. The control knob seems to have no effect even if I switch it right down close to off. The fan and the quick cool buttons seem to work.
I can call an engineer but wanted to check first whether there was anything that I could do to fix it possibly. Also how do I go about finding an engineer that can fix Liebherr fridges?
Thanks a lot,
Julia.

[Electrocoolman]

Julia,
If it has a quick cool button then that would possibly suggest that it has an electronic contol circuit, rather than a conventional thermostat.
You could try unplugging (or switching off at the mains) and leaving it for 5 mins, and then switching back on.
When you press the quick cool button, do you get any indications that the button has been pressed?..i.e. an indicator....I take it that this button is not permanently stuck in (or indicating) ?

Failing anything simple...it could be the sensor or the control board. Does this unit have a temperature display?

Regards.

[jlovick]

Hi Electrocoolman,
Thanks for replying, the quick cool button has a light on it and it also changes the temp indicator to 1 degree C indicating that it is going to work on its highest setting. It isn't stuck in and releases normally and the temp indicator goes back to 7 degrees C.
I did try exactly what you said and unplugged it, left it until the ice melted and switched it on again but pretty quickly the back plate had ice starting to form again and the compressor was not going off. (Working in IT support the off - on was unresistable to me as a potential fix!).
Do you think the back of the fridge being dusty could affect it? I haven't pulled it right out yet but I have a lot of spiders in my house and they can tend to build up web and dust etc - is it worth getting it out and cleaning the back? Or do you think it's just the control panel - I'm sure it will be electronic as it is an expensive new fridge (and German).
Julia.

[Electrocoolman]

Further to my previous post,......

I have found details of your fridge...assume its a recent model with the 'Magic Eye display'....and yes it is electronic control as suspected.

One quick check is to see if the fan and door switch are operating. The door will operate a switch as it closes....it is probably at the top in the middle. Operate this by hand with the door open....the light should go out and the fan at the top rear inside the fridge should start up. If the fan doesn't run then this is the reason for your food freezing as the sensor (probably at the top of the fridge) is not sensing the cold air, so it thinks its too warm and is trying to cool it all the time.

If the switch operates by hand, you then need to see if it operates by the door action ....which could have dropped thus just needing adjustment of the hinges. Has the fridge been moved at all recently...the cabinet hasn't twisted and "gone out of square"....i.e. started to rock on its feet which might just require the feet re-adjusting to level it back up.

[richardb14]

sounds like a relay with welded points

[jlovick]

Hi,
I'm sure the fan works as I can hear it when the door closes and although it switches off when you open the door it is still going round as it slows down so that proves that one.
I'm not actaully with my fridge right now so I can't go and check the switch by hand but I will do on Friday when I'm there next. I would guess that bit is working which presumably leaves the temp sensor itself malfunctioning - what do you think?
If it looks to be that as I suspect after what you have said how do I get someone out to fix it? I'm in Suffolk.
Julia.

[jlovick]

sounds like a relay with welded points

any way for me to check/fix that?

[richardb14]

when the stuff is freezing what does the temp display read?

[jlovick]

when the stuff is freezing what does the temp display read?

The temp display was reading 5 but freezing stuff, then I did the off on test and now it reads 7 but is still freezing things. I have noticed that turning the dial up and down no longer seems to affect the temp display, before it used to flash up or down to the next temp setting as you turned it showing where you had set it to. Now it just stays on 7 but it is much colder in the fridge obviously.

[Electrocoolman]

Yes Julia,
There is only the sensor or control board really left. It could be the control switch for the compressor...(Relay/Triac) stuck or shorted....which again is a control board unless you get an engineer whose ability stretches to component level.

BTW...How old is the unit? Where did you buy it from?
My angle here is to check with Liebherr how long their warranty is, and some stores like John Lewis offer longer warranties.....just a thought.

The shop where it was purchased from should have service available, or Liebherr will have suggestions.

RICHARD: the 'display' would only appear to indicate the 'selected' temperature and not the actual temperature.

[jlovick]

Yes Julia,
There is only the sensor or control board really left. It could be the control switch for the compressor...(Relay/Triac) stuck or shorted....which again is a control board unless you get an engineer whose ability stretches to component level.

BTW...How old is the unit? Where did you buy it from?
My angle here is to check with Liebherr how long their warranty is, and some stores like John Lewis offer longer warranties.....just a thought.

The shop where it was purchased from should have service available, or Liebherr will have suggestions.

RICHARD: the 'display' would only appear to indicate the 'selected' temperature and not the actual temperature.

I bought it from John Lewis in Dec 2005 so over the 2 year manufacturers warranty and I didn't buy 5 yr extended warranty from John Lewis as my opinion was that fridges never break - oh how wrong I was!!!
Would John Lewis be able to give me a contact for an engineer do you think even though I'll be paying obviously.....?

[Electrocoolman]

John Lewis....Yes, I would hope so.

Also try Liebherr 084 44 12 26 55

[jlovick]

John Lewis....Yes, I would hope so.

Also try Liebherr 084 44 12 26 55

OK, great, I'll try them. Thanks for all your help, it is useful to talk through what might be wrong so I can eliminate obvious silly things that I might be able to fix myself.
Obviously German engineering isn't as foolproof as we're led to believe....

Julia.