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I’m having problems with a Liebherr NoFrost freezer, Service number 9987684-02. It was bought about 4 years ago. The high temperature alarm has gone off at -8 or -9 degC, it seems to be losing its cooling ability. It has been fault free up to now and it hasn’t been hit/banged/dropped/punctured, so far as I know.
I suspect it may be a loss of refrigerant; the compressor can be heard running, the condensor coil is only warm for about 1/3rd of the first loop up the bach from the compressor discharge and a couple of brazed joints near the compressor look nasty (flux and verdigris); obviously I don’t repair freezers and I don’t know what the fault actually is.
How would I locate a competent service/repair technician for one of these? Is Liebherr specific training recommended, or do I just stick a pin in Yellow Pages? IG8 Woodford, Essex area.
Is a new compressor the standard fix for this (if it is leaking) or would anyone find and repair a leak and re-gas it?
If a new compressor is needed, what vacuum should be applied, to remove water or non-condensable gas, before re-gassing and how long should it be applied for?
Any advice gratefully received.
I’m not convinced it has completely expired yet; the temperature display can only be seen by opening the door and I’m keeping the door shut for a few hours to see if the temperature comes down.
Re: LIEBHERR NOFROST FREEZER
The first thing to try is find someone to look after your food for a few days.
Turn of the freezer and leave the door open for 48 hours.
Turn it back on and if it returns to the normal temperture within 24 hours you can put your food back in.
If this works but the fault returns within 2 months then it will be a fault with the defrost system and will need an engineer to repair it.
You can search for an engineer on this site if you need one.
Bob
Re: LIEBHERR NOFROST FREEZER
First, thanks for your advice Bob, it is much appreciated.
Secondly, I left the freezer off overnight but didn’t thoroughly defrost it as you’d recommended. There is still too much usable food in it to do that.
I turned it on this morning. The compressor started as usual but the condensor coil remained mostly cold, so there was little heat being shifted. After 5 minutes there was the sound of another motor starting, an internal fan I’d guess; this hadn’t happened previously. The condensor immediately got warm and the freezer started working again. After 7 hours it was at -15 degC, the fan noise had stopped but the compressor still seemed to be running. Setting the temperature down to -17 set the fan running again. There was less than a cup of water in the drain tray above the compressor.
So I was wrong. You were right. Thanks.
I’m quite annoyed about this; I’ve got an expensive freezer that might stop working every 3 or 4 years at random, ruining £100 or £200 worth of food and losing me more time off work. I’m wary of loading it up again in case it stops. I couldn’t get a technician to look at it, presumably because it has electronic controls and is too complex for them. The repairers Liebherr recommended are around the other side of London. Katenutt’s recent post seems very similar. If this is a known problem, why don’t they tell users to defrost it every 3 years or recall them?
Re: LIEBHERR NOFROST FREEZER
Liebherr are normaly one of the best frost free fridge/freezers you can buy.
As soon as possible you will need to fully defrost the freezer as you will still have ice present.
Then it will be back working 100{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d}.
If the problem returns within a couple of months then you will have a problem with the defrost system.
The electronic controls on Liebherr are very reliable and rare to give a problem.
The most likly fault would be a freezer evaporator sensor and even on the most expensive fridge/freezers if moisture penatraits the sensor it can fail.
On some makes of fridge/freezer the sensors cannot be replaced and then not repairable, but on the Liebherr
most parts are available and it is rare not to be able to repair a Lieberr.The fan cuts in only when the temperature drops so as after a defrost it will not blow warm air around the freezer, this is why the fan did not start up when you first turned it back on.
Sometimes with a frost free if you have a short power cut it can fool the control panel or if the door has not been fully closed then too much ice builds up and is sometimes more than the defrost system can cope with and starts of the problem.
If you fully defrost it hopefully the problem will not return.
Bob
Re: LIEBHERR NOFROST FREEZER
This has happened again. The freezer ran for about a week and the stopped again. I have now completely defrosted it but it shows no sign of restarting. The internal fan used to run for a few seconds after the door was closed (judging by the sound) but this no longer happens. I can see a part of the evaporator, which gets frost on it, so it looks like the fan has failed or it is being held off for some reason.
Could someone please advise me how I can get access to the fan and the sensors? It is not obvious how to remove the plastic trim without breaking it. I’m an engineer and have much experience with electronic BMS controllers, thermistors and controls for 230 & 415V equipment. Any guidance would be appreciated. Can the Comet repair service be recommended? Thanks for any assistance.
Re: LIEBHERR NOFROST FREEZER
Update; I got an engineer out to look at it. He got access to the fan and the evaporator and then announced it was either the PCB or the fan, said he’d have to speak to a colleague and left. He said he’d ring me back on Friday to arrange another call. He didn’t.
The occasional crack as he worked on my expensive Liebherr was an ominous sign.
The only reason I hadn’t attempted a fix was that I didn’t know how to get access to the components under the plastic trim, but since he broken those bits for me and it’s scrap if I don’t fix it, I’m now working on it.
The fan works, there’s no power from the PCB. Can anyone advise me what the resistance of the air temperature and evaporator thermistors should be at about 21 degC? I have two very different values, 2.8 & 5.9 kOhms, which seems odd; every control system I’ve come across has used thermistors with the same values. Anyone know what these should be. I will emit waves of gratitude and good karma to anyone who helps, the wife is going to kill me if she doesn’t get a freezer soon.
Re: LIEBHERR NOFROST FREEZER
hello onetap, it’s a shame that the repair wasn’t completed or that at least you didn’t get some satisfaction from the engineer’s visit.
it’s always hard to give a definite diagnosis from this side of the keyboard, as opposed to a hands on inspection, but i’ll try and shed some light on your situation.
i despair at the ‘turn it off for 24/48 hrs’ answer. the only time that this approach has any effect is if the door has been left open, allowing the evaporator to over ice. all other times, it just serves to prolong the problem and the associated inconvenience.
the readings from your sensors should be about the 5.9k ohms at 21c. 2.8k ohms would ordinarily suggest a temperature of over 35c.
so, in terms of probability, it seems that you have a sensor fault. (part no: 9590148) the part number is the same for both sensors by the way.
the evaporator fan will not run unless the evaporator is cold. it used to be -15c, but that has recently been changed with the advent of the new sensor kit.
the electronics in the appliance require the evap temp to be a few degrees colder than the air temp inside the cabinet before the fan gets feed from the pcb.
that’s my two penneth from here anyway. of course, you could have a problem with the system or the fan, but these are both unlikely. you could also have a problem with the pcb, but i would say that a problem with a sensor is much more likely than a problem with the pcb.
hope this helps.cheers.
Re: LIEBHERR NOFROST FREEZER
It does, Mr. Uckem. New sensor tomorrow and see what happens. I will report back. Many, many thanks. OT
Re: LIEBHERR NOFROST FREEZER
Update; fixed, evaporator sensor. Sent by Liebherr within 24 hours. Many thanks to samuri and Alf Uckem for their assistance.
I was able to fix this by lowering the evaporator module at the top of the freezer; the instructions say the module can be pulled forward but it seems to be restrained by the refrigerant pipes at the back. It there enough slack in the pipes to pull the module forward?
However, some thoughts on this unhappy experience. My previous encounter with thermistors was in BMS systems. One installation I was heavily involved with had 100 or 130 outstations, and those outstations could have just 2 or 3, or up to 40 analogue inputs, which were usually thermistor temperature sensors. There were probably over 1000 thermistors on that site, immersion, duct sensors, wall mounted, outdoor. Now, it’s a long time since I was there, but i don’t recall thermistors failing. I’m sure there must have been a few in 10 years, but I can’t recall any. Humidity sensors, especially the early ones, were fragile. Thermistors lasted forever, but those weren’t operating at -20 or -30.
Having read someinternet posts, the sensors are a common cause of failure. Surely the encapsulation on these must be defective? Why else would they fail?
Then, £30 for a sensor? Is that usual (“trade price”)? A bare thermistor is 50p and £10 or £20 when in a shiney plastic wall-mounting package. There’s no way a bead thermistor should be £30, especially when it is to replace apparently defective components.
Finally, i was thoroughly unimpressed with both the Comet (10 days!) and the Domestic and General fixed price repair services. The latter sent some man who levered bits of the plastic trim off the back, didn’t get access to the PCB and didn’t diagnose the fault. I asked them to repair the damage and they said they’d ring me back; they haven’t. Shabby, incompetent and unprofessional service.
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