I have the old type cf50 the one with LED temp lights.
If I run it in emergency it will get down to around -15 deg so the gas and compressor should be ok.
The problem is as soon as I run it off of emergency it will run for a minute or so until it reaches some sort of temp, it is cooling though, and then stop's and the green power on light goes a yellowy greeny colour.
No other light's come on, just the power light changes colour.
Then if I press the temp button up one more light, the compressor start's and run's until what ever temp and then stops again and the power light does the same thing.
This will happen on each led getting cooler every time (goes down to about 8 deg until I have increased the temp setting one light at a time to the freeze led and then it stop's and won't work until I have turned it off for a while.
I can go through the same thing and it will do this every time I try it.
Any one have any idea's where I should start with the fault finding, all help will be greatly appreciated.
Its most likely the thermistor or the Main PCB. The thermistor should read 10K ohms at 25deg C when checking with an ohm meter. If its the main PCB then they appear to be available from Top End Cool in Darwin for $170 on Ebay. Picture of the PCB from there site. A cheaper option is use an electronic thermostat to replace the PCB for about $12 on Ebay if you are adventurous.
Thanks DeBe.
Where is the easiest connections point to check the thermistor.
If I go the new electronic thermostat, can you tell me the seller for the one you show I the picture then if I have any problems fitting it at least you will know which one it is I have used in case I need you help again.
Thanks again.
Russ-t
Will need good clear photos of the Main PCB, both sides & the wiring going to it. The Thermistor will be pluged into one of the 2 pin conectors of the board.
Think I have got the thermistor, CP4, will double check on some of the drawings that have been posted.
My ohm meter is set at 2000k and the reading I am getting is 332 ohm with a fridge internal temp ( fridge not running ) of 20deg taken with a thermometer inside the fridge at the bottom, is that what you meant about 10k @ 25 deg c
If that reading is correct and the thermistor is shot it looks like it is easier to go the electronic thermostat than trying to dig out and replace the old thermistor , after watching a few youtube's it looks quite a lot of work.
if I go the new thermistor way can the thermistor be put in via an easier way or would it be better to go electronic which would remove all the old electronic stuff in the fridge getting rid of possibly more faults
A couple of questions first. Does your fridge have a built in 240v ac power supply? If not is it only ever going to be run on 12V DC? Do you usualy use it as a Fridge or Freezer? Yes you can fit a thermostat in an easier position. To check the thermistors resistance you need to un plug it, as theres resistances in the circuit board that will give a false reading. Picture of a 10K thermistors reading at 19.5 degC. Does your controller on the compressor look like this? Can you post a picture of it. (Pictures are essential when describing a project as all model fridges are not necessarily the same) Also insert the pictures as thumb nail pics are difficult to work with, prefer JPEG.
