Auto reset circuit breaker problems; why we wont use them again
On the second day that we’d pulled into Broome, I woke early one morning to find my new Bushman 85L Upright Fridge had turned off in the middle of the night, and it had defrosted the ice around the freezer, and I had a big puddle at the bottom of the fridge, through our food and outside of the door seals.
After reading the manual, I could only put it down to excessive frost build up, but even Bushman couldn’t explain why the fridge would have turned off.
A week after the unplanned defrosting event, I heard the compressor on the fridge shut down with a similar pinging noise, and not long after noticed the LED light go out, which means the fridge is getting zero power.
I stood there for a while, contemplating what could be wrong, and what we’d do for the rest of our holiday, with the ambient temperature hovering around the 35 degree mark. I checked the Anderson connections were OK, and that the 15 amp fuse fitted in the fridge wiring hadn’t popped, before moving onto other options.
Each time I swapped the Anderson plug to a new one, it would run for some time, before the pinging noise and the light would go off again. Finally, I realised that one of the noises was coming from my electrical panel, where the Projecta DCDC lives, and a number of fuses/auto reset circuit breakers.
I opened the box, and sure enough, could hear the clicking noise of an auto reset circuit breaker resetting and then the fridge would come on again.
To double check this was the issue, I put my finger on each stud of the breaker, and burnt the tip of my finger on the one the fridge was running from. Lovely. On one of the Andersons I have for supplying electronics, I noticed that the fridge light would flicker too, which meant the supply was inconsistent.
Now, I’ve had the nuts on these circuit breakers come loose in the past, and it means there is poor contact between the cable lug, and the breaker itself. This in turn creates heat, and you end up with performance issues, or it just doesn’t work at all.
I grabbed a tool kit, and sure enough the nuts were loose, presumably from the nasty corrugations we’d done in the trip at Millstream National Park, and James Price Point.
After tightening all of the nuts on the auto resetting circuit breakers (5 of) I plugged the fridge into a few different Andersons and gave it all a whirl. No more flickering lights, and no more fridge tripping out.
All in all, frustrating, but at least it didn’t taint our Bushman Upright Fridge Review, asides from the frosting issue that we still haven’t resolved.
If you are considering moving to an upright fridge, there’s lots of pro’s and con’s (like usual); have a read of this – 12V upright vs chest fridge.
Circuit breakers can either be manual reset, or auto reset. The manual reset requires you to press a button on the side to re-engage them, and the auto ones just use a bimetallic strip that heats up to a point where it disconnects, and then as it cools it reconnects automatically.
These are good for some applications, but in others you’d rather know that something is wrong before it caused further issue.
Given how hot these were (they’d partially melted the plastic covers), you have to wonder what the chances are of a fire from them. Not something you’d want to be dealing with, and after being woken by a 12V fire not too long ago, its not something I want to deal with.
These auto reset circuit breakers are compulsory on things like your trailer brakes, so if the circuit trips out it resets automatically. If you have them in your vehicle, grab a spanner or socket and check they are tight. Don’t overtighten them as they’ll pull through, but they need to be tight enough.
For us, I think I’m going to get these removed in place of actual fuses.
