Club 80-90 Forums

Hello, we have noticed our fridge doesn't seem to keep a steady temperature. I have been doing some research and have noticed that certain models where fitted with a fan that blew over the fins of the fridge.

I am happy with fitting a computer-style fan and a switch to control it but I'd want to put a thermistor through the live feed to the fan so the fan only came on when it hit a certain temperature. The thermistor would be screwed/riveted to a fin on the back of the fridge. I think this set-up was standard on certain fridges my question is does anyone know where I can buy this thermistor? And if not does anyone know of a thermistor i could buy that would be rated correctly (works at 12V and comes on at ??degrees?)

Here is a link to a picture of our fridge:
http://www.mkcaravans.com/electrolux_rm212_fridge_1.JPG" onclick="window.open(this.href);return false;

Cheers!

I really should know this.....it's doing my head in...ahhhhh!!!!

These are definately available at Maplins...I remember that from a previous thread...I can't for the life of me remember the temperature but it's a thermo switch, and only switching about 0.2 amps at 12v...my guess would be around 50C although something in the back of my head is saying much higher..like 80C.
When you think about it, lower is better as long as it goes off when the fridge is not in use...50C should do it.

Martin

Hi, thanks for the reply Martin. I called up to Maplins today and they don't have any thermistors other than "bead" thermistors, i think they are more for ambient temperatures and they only went upto 25 degrees c anyway.

http://i243.photobucket.com/albums/ff66 ... photo6.jpg" onclick="window.open(this.href);return false;

http://i1180.photobucket.com/albums/x41 ... 0928-1.jpg" onclick="window.open(this.href);return false;

Above is what i'm after, I take it this is a thermistor unless it has a different name?

That is a 'Klixon' thermal switch - a thermistor is a resistor and its value changes with changes in temp. - it is used for switching small loads and would normally need a relay for a reasonably powered fan.

Thermistors on my workbench:

Ah! Thanks, so is klixon the brand name? And i don't suppose you know the model number or temperature rating of the thermal switch needed for the RM212 fridge do you?

Thanks alot.

I just noticed this, normally closed - which I assume means it opens when it's 50 degrees or above, which of course will then give power to the fan.

http://www.ebay.co.uk/itm/THERMAL-CUT-O ... 1149wt_906

or

http://www.ebay.co.uk/itm/Thermal-Cut-O ... 1667wt_906

You think that'll do it?

No you don't need a NC type.
You need a normally open (NO) type as you want the power to flow when the temp. reaches the required setting.

Yup...normally open meaning open circuit..... then closing (completing the circuit to bring on the fan) when it reaches it's designed operating temperature.

Like this:

http://www.ebay.co.uk/itm/Thermal-Cut-O ... 43b25441b4" onclick="window.open(this.href);return false;

Martin

Ah yes, seems obvious now, i was thinking closed as in the flow of current was closed, okay i'll buy the parts and do this mod on the fridge then.

As ever thanks for your help!