Fan fridge

[Theo Markettos]

I have an old non-frost-free fridge, which is mostly used for storing freshly-picked fruit. The trouble is, it's not very good at cooling when the fridge is full. The fruit at the back is frozen solid (since the back turns into a sheet of ice in not much time), the fruit at the bottom in the 'vegetable' well isn't cold at all and starts going mouldy (I've removed the glass shelf above it)..

Since you can get fan ovens, I wondered about a fan fridge. I could replace the bulb with a 240V fan, and muck about with the door switch to make some kind of thermostat (relay/triac across the switch contacts plus some low voltage sensor, perhaps)

Can anyone see flaws in this plan, or make any suggestions?

Cheers, Theo

[Dave Liquorice]

The fan will disipate most of it's energy as heat, inside the fridge which the heat pump will have to move to the outside. As it's not working very well at the moment...

I think you'd be better off not packing the fruit in to the extent of stopping the air circulating via ordinary convection.

[The Natural Philosopher]

ever seen an iced up fan?

:-) You will..

[Alan]

In message , Theo Markettos wrote

My larder fridge has a fan. A larder fridge has no ice box and in my model the fan is mounted at the top.

[Bolted]

What sort of fruit?

[Theo Markettos]

Cherries and plums. It's only temporary storage until I 'deal' with a dozen or two kilos for fruit, but that takes a little while. Cherries were in carrier bags (since they'll otherwise fall through the shelves: I might try putting plums out directly. One source of icing is they tend to breathe moisture, especially if any leaves came too.

On the point of fan power consumption, it's rather higher than I expected. A

12V 'high performance' fan from RS takes 3.6A. Ouch! That might be start current, it isn't quite clear. Another random PC fan is rated at 5W, which is rather more sensible but still a bit high. Of course it wouldn't be running all the time and (subject to PWM) wouldn't be running at full speed either.

Theo

[NT]

3-4" PC fans eat 1w upward. It would certainly help. It would be easier simply to put the fan on very thin flex, eg a pair of cores of ribbon cable, and close the door on teh cable. Wallwart to provide the 12v or 9v etc.

Something more ventilated than teh salad crisper and teh carrier bags would also help.

NT

[Mark]

+1

[RobertL]

Perhaps it's just that he's putting in the fruit without wrapping it. Maybe the moisture comes from the fruit itself drying out.

Robert

[Adam Funk]

The OP could mount the motor on the outside and a run a shaft through the case to the impeller on the inside, but that's a lot of work compared with your suggestion.

[Theo Markettos]

Some does. And if there are leaves in there, they breathe quite a lot. Particularly when picking cherries, sometimes it's easier to pick a whole bunch plus leaves than individual fruit.

The fridge already has compressor problems (it doesn't always start if it's been switched off for a while) and is fairly decrepit anyway, so it's just a temporary arrangement for a few weeks while I store fruit.

Theo

[Mr Pounder]

How old?????

[Theo Markettos]

1993ish.

Theo

[fred]

In article , Theo Markettos writes

Other arf has a Bosch fridge freezer with fans in both compartments and it is bldy brilliant, known as the miracle fridge for even temp and keeping stuff fresh way beyond theoretical limits, I'd say go for it.

Only fly in ointment is that mains fans are generally for higher power air shifting so tend to overkill in your app. If your app was a PC I'd be suggesting '7 Volting' a 12V fan to get just a gentle circulation of air, might work for you and fine wires could probably bypass the seal with little leakage and pass to an external supply.

[Alan]

In message , fred wrote

Thermostat controlling on/off. A computer fan on for a few minutes every so often is not going to take much power and using it at full speed is going to equalise the temperature quicker.

[Andrew Gabriel]

... you have filled the fridge with fruit (water).

That's a problem with storing fruit in a fridge - A fridge will dehydrate anything which isn't close wrapped, including fruit. A fan will help even out the temperature, but it will also dramatically increase the drying effect, so you want it to be as slow as you can get away with. You don't need it running at

4C either - doctoring it to run at 10-12C would probably be fine for fruit and reduce the drying effect.

To be honest, I doubt you'll gain much (if any) extra life from the plums by refrigerating them.

[Man at B&Q]

Does it have a "fast freeze" shelf. If so then you need to learn to use the appliance in the way it was intended to be used.

MBQ

[Theo Markettos]

It's a fridge, not a freezer. There's a freezer compartment but this is part of the problem: the flap isn't sealed, so tends to ice up and eventually stop the door from shutting. Not got that way yet, but it's quite annoying.

Theo