Waeco cf40 coolbox repair

[Phill]

It works perfectly on 240v but when I use it on 12v, the fan runs, the compressor doesn't, and the red error light flashes. I've checked and have between 12.5. and 13.7V at the socket into the coolbox so guessing it's an internal controller fault. Anyone have any experience of repairing these as I'd rather not replace it with a new one.

 

[PowerSlapper]

It works perfectly on 240v but when I use it on 12v, the fan runs, the compressor doesn't, and the red error light flashes. I've checked and have between 12.5. and 13.7V at the socket into the coolbox so guessing it's an internal controller fault. Anyone have any experience of repairing these as I'd rather not replace it with a new one.

"12.5 and 13.7V at the socket" does not mean much except you can get voltage at that point. You could still have a bad connection further up stream or even between the plug and the socket on the unit. I had a similar problem with a radio, plenty of Volts but when trying to transmit not a lot happened. Checked the volts on the circuit board where the power leads connected and got 12.7 - keyed the Tx and volts dropped to ~3V which is not enough. Traced the power leads back and found a very badly corroded inline fuse (not sure why this had been installed) Cut the holder out, soldered the wires back together and all was well in the Tx dept.
If it was my unit i would open it up and measure the volts under load where the DC leads attach to the control board. The fact the unit runs happily on 240v would indicate to me a fault with the 12V supply. The compressor will be 12V (or less) with the 240V being rectified and dropped to 12V. Stage 2 would be to start at the compressor terminals and work back to isolate where the lack of V's is occurring.
iIRC these cool boxes sense incoming volts when on 12V power and cut out if they sense less than 11 or 11.5V and display an error (low voltage) light.

 

[BobnLesley]

It works perfectly on 240v but when I use it on 12v, the fan runs, the compressor doesn't, and the red error light flashes. I've checked and have between 12.5. and 13.7V at the socket...

Before pulling things apart, I'd try connecting the fridge directly to a good 12v battery with some heavy wire. We've found thay they need a good flow of sparks initially just to get the compressor to kick-in, so if you're plugging it into a cigar-lighter socket or similar, it may well be that the wires feeding that socket are too lightweight.

 

[C08]

I would support the comments made about voltage. MY CF35 does not work with a 12v plug but is fine hard wired into the 12v. Also have you got the battery protection level on the cooler settings set too high eg 12.5V such that when it is on the voltage drop (sucking up 5 amps probably more at start up) makes the cooler "see" less than 12.5v and shuts down instantly i.e. does not start up. I had all these problems when I first got my cooler 6 years ago but after initial learning how it behaves and adjusting settings etc it has been perfect since running 3 months each year. Good luck with it.

 

[KAL]

Agree with previous posts. It's about how much voltage the unit sees. The sensor will cut out to protect your battery level. Had the same issue and IIRC, had to upgrade the wiring supplying the 12v socket to reduce voltage drop.

Sounds like the unit is operating as it should. Def worth checking what CO8 suggests as well, as there are user-adjustable settings.

Good luck.

 

[C08]

Agree with previous posts. It's about how much voltage the unit sees. The sensor will cut out to protect your battery level. Had the same issue and IIRC, had to upgrade the wiring supplying the 12v socket to reduce voltage drop.

Sounds like the unit is operating as it should. Def worth checking what CO8 suggests as well, as there are user-adjustable settings.

Good luck.

yes, I had to connect direct to the battery.

 

[Phill]

Thanks all. I have had it connected directly to a new battery which was also connected to a charger. I used both the supplied lead and a heavy duty cable. I know I've had at least 13v at the socket on the side of the fridge. All the switches are in the correct positions and the same positions it used to work in. I think the fault must be in the electronic box inside the unit but don't think it's a serviceable item.