12v Fridge: moving evaporator plate lower?

Tim Good

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I have a large side opening fridge in boat with a 12v Frigoboat keel cooled system. I have a fan in the fridge to keep air circulating. However with two large side opening doors I feel a lot of cold air falls from the fridge and I struggle to keep it below 5c even on max setting. I do try and keep the upper shelves full of water, beer or other things to keep it full and prevent cold air from falling out.

The design of the fridge is such that the lower portion is below the opening of the doors so that cold air would remain in the bottom whilst the upper half parallel to the opening doors. My evaporator plate is as high as possible in the fridge.

I had read somewhere a while ago that I could move the plate lower down in fridge, which would have the effect of keeping the lower section cool below 5c and warmer in the top. The suggestion was that the fridge would be easier to keep cold in the lower section were I'd keep meat andnso forth. Beer water can go in the warmer upper section.

Does anyone think this would work?
 

macd

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However with two large side opening doors I feel a lot of cold air falls from the fridge and I struggle to keep it below 5c even on max setting. I do try and keep the upper shelves full of water, beer or other things to keep it full and prevent cold air from falling out.

The cold air falling out issue is real, but often massively overstated. I worked it out a few years ago and can't be bothered to do so again, but IIRC cooling 1litre of water by x degrees involves the same removal of heat as cooling well over 3000 litres of air. So, for a typical 100litre boat fridge, equivalent to about one tenth of a small bottle of beer. Obviously, if there's anything in addition to that miniature beer in the fridge, the equation is progressively more favourable.

Nonetheless, moving the plate lower would certainly encourage the area under it to stay colder.

Our plate (also with a keel-cooled fridge, but top-opening) is quite high up, but box shaped. The area below it is perfect for cold ones. The box itself freezes effectively, helped by a curtain of vinyl at the open end of the box. (Off-cut from a sprayhood window.) It took a little experimenting to refine the appropriate degree of "cold leakage" from the box, but now works well.

Good luck. The importance of cold ones cannot be overstated :encouragement:

Edit: brain-fade earlier. Text in bold added.
 
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sailaboutvic

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At last our fridge is working 100% and our O type plate freezer any thing that in it , one suggestion is if you can't get it to stay below 5c on the lowers setting then more the thermostat sensor which are normally on the bottom of the plate to the top .
 

ShinyShoe

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And does the fan switch off when the doors are open?

And is there a light - is it LED or filament and does it switch off when the doors are closed?
 

Tim Good

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And does the fan switch off when the doors are open?

And is there a light - is it LED or filament and does it switch off when the doors are closed?

Fan is manual but I hear what you say. It should ideally not be in when I open the door. No Light.
 

ShinyShoe

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Fan is manual but I hear what you say. It should ideally not be in when I open the door. No Light.

It makes a difference. Should be easy enough to wire through a magnetic relay with a door magnet.

Been surprised at effectiveness of those plastic curtains at keeping big walkin fridges cold. Being a tight git - I'd be tempted to build something similar on a small scale. Overlapping strips of clear plastic. You only create a gap big enough for an arm and the object going in or out.
 
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