Zanussi ZI918/8K Fridge Freezer compressor running continuously and too cold

[enjoy_life27]

Hi all,

I have a Zanussi ZI918/8K Fridge-Freezer about 10 years old. The problem is that it seems to be running continuously and too cold in fridge and freezer both building up ice along the back wall.

Spoke to one of Engineers who suggested it is the thermostat which must have gone. I have now replaced the thermostat with genuine Zanussi one for this fridge-freezer but it doesn't seem to have made any difference. The new thermostat is set to around 2 and a half.

The freezer is very cold and the fridge is very cold too building ice on the back wall. I would have expected the compressor to be switched off every few hours but it doesn't seem to be the case. I have also got high electricity bill for last quarter and thinking the fridge might be the culprit (as everything else is energy saving stuff in the house).

Looking forward to your help guys. Thanks in advance.

[1mikeefc1]

Does the compressor knock off when the stat is in the off position?

[enjoy_life27]

Yes the compressor does knock off in off position or just below 1 position.

[TERRENAS]

Maybe the capilary probe of the new thermostat isn´t in right place, you have to measure the old one and insert the same length on sleeve...

[enjoy_life27]

Is there any easy way to find if the capillary probe is at the right position? Any sound, click, visual? The length of the capillary is the same on the new one as its an original part.

I have put the capillary inside as far as it goes. I read somewhere else that maybe the capillary holder on the evaporator has come off giving it false reading. Is that possible? If yes, how to check/fix that? The capillary tube goes all internally when you put slide it in on this model so I have no way to confirm where it is meeting at the other end.

Pls help as I am really going mad with this now and badly want to fix it. Thanks in advance.

[1mikeefc1]

Still sounds like a faulty stat to me, try removing the capillary on the stat and putting it in ice cold water to see if the comp cuts out on a medium setting. If it the comp still runs while the capillary is in ice it's either wired wrong or your new stat is out of range.

[enjoy_life27]

Well the problem is that the new stat is behaving pretty much the same as the old stat which makes me think the stat was probably fine in the first place. There is no specific direct wiring to the stat on this model, it sorts of gets plugged into position in the slot so cannot be wrong.

And the capillary not be positioned properly in evaporator for whatever reason be a possibility? Or as someone else mentioned, can it be a low gas or compressor fault?

[1mikeefc1]

If it was a compressor fault or a gas issue it would be warm not over cooling, the position of the capillary is a possibility but if its gone in as for as the old one came out it sounds like you've placed it correctly. What happens if you leave the stat set at 2? It will need to run for a good amount of time to cool down but I would expect the comp to cut out.

[enjoy_life27]

If I leave the stat at 2 and a half (as currently set), it keeps running almost all the time and ice starts to build up in the fridge and back wall - gets more and more thicker with time (say 1-2-3 days).

I doubt it actually does switch off even once in 2-3 days else the ice inside the fridge should defrost. At the moment, I manually move it below 1 every couple of days (and then back up), which cuts off the compressor and triggers the defrost function. The compressor then stays off for 2-3 hours, the ice inside melts (with doors closed and fridge switched on). There is also noise of ice falling down from behind the fridge when this happens.

Any more suggestions to get this thing fixed will be highly appreciated.

[1mikeefc1]

Have you tried putting the capillary into a glass full of ice and seeing if it knocks off? This will confirm your stat is working.

[enjoy_life27]

Right then... the thermostat seems to be working alright... have checked it by above method.

What else can be wrong? Someone said Low on refrigeration gas? Someone said defrost for 2 days (dont know how to manage without fridge for 2 days)? Someone said replace it as cannot be cheaply fixed?

Not sure what to do next.. any help/advice will be kindly appreciated.

Thanks.

[1mikeefc1]

Can only suggest a full defrost for a couple of days, you've proved the stat is ok and I would say low on gas wouldn't cause icebuilding up as you describe. Other than that and I'm out of theory's sorry.

[TERRENAS]

If thermostat is ok, only left 3 possilble fault... a faulty compressor, a gas leak or the capilary sleeve is separate from the evaporator ...
Which achieved temperature in the frige ?
Put your hand in the middle of the condenser, is it hot?
It should be hot, about room temperature plus 17ºC.
You cant test the thermosthat by ice method, the cut in/cut out is far below 0ºc.

[enjoy_life27]

Temperature in the fridge gets to around 0 degrees and in freezer to -22 degrees.

The appliance is integrated so guess I cannot touch the condenser unless I take it out?
So if it is a compressor fault or gas leak, I reckon it is not worth economic repair then? Capilary sleve separate from evaporator - have been thinking abt this. Any way to check/fix this?

Also for my knowledge, what will a full defrost (say for 2 days) achieve? The problem is its a big pain to do as it means to be without fridge for the family for 2 days - so almost impossible and will only take this step if there is a strong possibility that this might help.

[1mikeefc1]

If your fridge is icing up and isn't fully defrosted before you changed the stat it will freeze up again very quickly because it's already got ice there. Does sound possible that the sleeve isn't sat in the correct position as you've already proved the stat works as for how to check it would mean pulling out the cabinet to locate where it is. I know its a pain to have it off for a long time but it needs to be clear otherwise your peeing in the wind.