Zanussi ZNB 3450S Fridge Freezer not cold enough

You will need a service call for diagnosis and repair. It could be a faulty thermistor (electronic temperature sensor), or it is low on refrigerant gas and needs a top up. Gas is the most likely reason. Make sure the freezer isn't on an Eco Mode that only deep chills the bottom, and useful if the freezer is nearly empty.

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Hi, it sounds like the fridge thermostat needs replacing.

pull the panels inside and check the fan usually in a fridge freezer the fan cacks out or is full of ice clean it out and clean the overflow tube if fridge is cold enough then it is the freezer fan

Many residential refrigerator / freezers are designed to work at temperature considerably above above freezing. Most modern refrigerator / freezer have a single electric thermostat - located in the fresh food compartment. This lone thermostat will control the compressor to keep the fridge (fresh food) section at the desired temperature (usually between 34 - 38 degrees F). The freezer will get colder regardless of how cold it is already whenever the fridge thermostat turns the compressor on.

Now that you see how the thermostat works, let's look at what happens when the fridge is placed in an unheated space - like a garage. In winter time, the temperature can drop considerably below 38 degrees. If the outdoor temperature remains cold enough, for long enough - it will affect the thermostat in the fridge. The temperature inside the fridge could drop below 38 degrees, preventing the thermostat from telling the compressor to turn on. Meanwhile, the temperature in the freezer compartment slowly rises from the normal -10 to 0 F degrees. It will continue to rise until it is the same temperature as the fresh food compartment or until the thermostat in the fresh food compartment tells the compressor to turn on again. This means the freezer contents will thaw.

If the temperature in the garage is even in the 40 to 50 degree range, the loss of cold in the fridge may not happen often enough to keep the compressor coming on often enough to keep some freezer items frozen solid - such as ice cream. Remember, water freezes at 32 degrees F, other products may require lower temperatures to remain frozen, and could thaw at 28 or other temperature.

Good luck!

While it could be the main control board, I would check for a defrost circuit failure first. If you take off the read shield of the freezer you will be able to see the evaporator coils. If that is a block of ice, then your defrost circuit is not doing its job and the ice is causing the thermostats to read the incorrect temperature.
The good news is that once you defrost the unit, you will have 2-3 weeks before the ice builds up enough to be a problem again. Which give you time to troubleshoot and order the replacement parts.

You have a defrost or temperature control issue or both. I will be back soon with photos and solutions. Thanks, Sea Breeze

i have had the same problem, it was the fan which needed to be replaced.

same here. have the znb 4051s refridgerator. freezer works fine but fridge does not. there is no sound eminating from the fridge either...any ideas? its 1 year old!

Re. Zanussi ZK87/46EFS Fridge Freezer

The same symptom occurred in our fridge freezer. The fridge compartment warmed up whilst the freezer compartment continued to keep temperature.

The cause of our problem was diagnosed as a frozen sensor that controls a flap, that controls the flow of cold air from the freezer compartment up into the fridge compartment. We were advised to power off the fridge freezer (removing all food and trays from the freezer unit first), and to leave it to defrost for 24hrs. We needed to place a few towels on the floor of the freezer compartment to soak up the melt water. After 24hrs we followed the power up instructions in the manual (versions are available online if you have lost yours). Within a few minutes it was obvious that the fridge compartment was being cooled – Problem solved :)

The defrost cycle is not happening like it should, that's what causes the block of ice (and poor air flow). If you have all that defrosted look at the defrost bi-metal, it usually is a small round disk with a couple wires coming out of it and it's clipped on the coils. When it's cold enough, it passes electricity to the heat elements, when it gets hot enough it "opens" and kills power to the heat elements. If that is bad (swollen cracked or bloated) and not passing electricity to the elements that's the problem. Another item would be the defrost timer itself, if it doesn't work (no clock motor turning) then it will never go into defrost. And the last and usually least expected failure would be the heat element themselves not working