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Re: The Insanity Is Amazing
It might look crazy… but we had a very similar setup a couple of years ago when we were helping one of our customers to prototype some new frost free appliances…
But it’s not the sort of thing I’d expect anyone to try at home!
I suppose that some Vauxhall drivers might have a “Cavalier” attitude to their appliances, but it could all end in tears if the appliance goes “Nova”!
Sorry, couldn’t resist the pun.
Re: Miele K2214S Thermostat
You’re not the only one to have been approached about flat-pack fridges. Some serious research is going on into this.
If this project does get going we would hope to supply the evaporators!
Cardboard fridges are already a reality. Ideal for merchandising displays where the same refrigeration system can be used again and again within a different display.
Regarding the original thread, I have a very strong suspicion that Liebherr and Miele are more or less the same appliances, if so, Coolectric, Nr Wakefield might have a part – 01977 665665, but no doubt at a similar rip-off price.
Peter
Re: Fridge Leaking Water
I agree entirely with the advice given.
To add some more information. The usual ISO testing for “built in” refrigeration appliances is in well insulated rooms and also with the appliance boxed in to simulate kitchen conditions. The appliance is usually placed on a wooden base some 30cm from the floor with an air gap under, i.e. not on a stone floor or against an outside wall. Whirlpool (or whoever brands these appliances) may not have tested in conditions similar to your description…
However your appliance is rated for a particular room temperature, and not the floor or wall it is placed on or against! As long as the room is within this temperature then the appliance can be expected to work OK. You can find the rating “SN, N, ST, T” on the rating plate (usually inside the fridge).
SN +10°C to 32°C (Extended Temperate)
N +16°C to 32°C (Temperate)
ST +18°C to 38°C (Sub Tropical)
T +18°C to +43°C (Tropical)My guess is that your fridge will be rated N.
You mention that the door might not be fitting properly, if this is the case, then more air than usual will be entering the fridge – and this air is relatively humid and this will cause more ice to build up on the back wall than usual, and hence more defrost water.
Your diagram shows a fan, I assume that this is running with the compressor… in addition to a warm condenser tube under or in the collector tray, it might be (it’s not always) that your appliance is designed so that the air-flow is blown across the collector tray in order to help evaporate the water, if this is the case there should also be some sort of venting in your kitchen units so that the fan has a good air supply and there is somewhere for the air + evaporated water to go?
Good luck with the Magnet and Whirlpool.
Peter
Re: Frost Free
Regarding ice build up. In evaporator testing and development, we consider 2 types of ice build up:
1. Primary Ice Build Up
2. Secondary Ice Build UpPrimary Ice, is ice that forms and is completely defrosted in the next defrost cycle. It is quite acceptable for this ice to melt and remain as water on the evaporator and not drip off… BUT IT MUST FULLY MELT EACH CYCLE.
Secondary Ice, is ice that does not completely melt during the next defrost cycle, and it then grows during subsequent cooling cycles. THIS IS INCOMPLETE DEFROSTING.
When you have to deal with a large ice build up, it is because of some failing of the defrost system…
There is one manufacturer out there that was shipping Frost-Free appliances without a correctly zoned heater. (With a low-wattage contact heater, the sort that clips into the fins). Within the heater there are different heat zones, but because there wasn’t enough heat put out by the heater at the bottom of the evaporator, ice will build up from the bottom of the evaporator. On this appliance, it doesn’t matter how many sensors you replace, it will still build up with secondary ice, this is because the heater is on for the full time of defrost and the cut-out sensor never warms up. The only solution is to change the heater, perhaps you guys are doing this unenviable job with those sharp evaporators!
That is just one example of what can go wrong. In some appliances there is a hidden heater, foamed in, under the gutter, if this fails then the gutter will fill with ice. It is also possible for the drain hole to block over time. It could take years for such problems to be discovered in the laboratory, hence the reason for problems in the field.
One model recently launched to the market has a three stage defrost, where for the 1st stage of defrost the evaporator heater and gutter heater are on. Then for the 2nd stage only the gutter heater is on. Then for the 3rd stage the appliance does nothing, and finally the cooling stage begins again.
Many of the newer electronic appliances sense evaporator temperature for two reasons. Firstly to control the defrost, and secondly to control the fan, so that the fan does not switch on, until, typically the evap is -12°C.
All this attention to control is aimed at one thing – minimisation of Energy Consumption, our customers are desperate to have appliances A rated. Unfortunately, the heater in a Frost-Free is a big part of the energy consumption and the OEM’s want to keep this to a minimum, so rather than guarantee the defrost by running the heater longer than necessary, the target is to minimise the use of the heaters.
I agree with comment on electronic control reliability. One manufacturer that I have dealt with revealed than a lack of anti-static precautions were causing many boards to be “zapped” during assembly and this is followed by early failure.
In the UK we are comparatively lucky to have a relatively low humidity climate and this reduces the ice build up on the evaporator. Defrosting problems are much more severe in the Far-East, South Africa etc.
Sorry if I’ve bored you all with tales of product design and development!Pete
Re: Frost Free
I work as a development engineer for a UK manufacturer of the evaporator found in a Frost-Free appliance.
We have tested Frost-Free appliances from all over the world and I have a good idea as to how these appliances work… and what can go wrong.
I can’t offer any guide or training, but if there are any specific questions about the evaporator or Frost-Free operation, then I will try to answer.
Peter
