AES Dometic fridge no switching (1 Viewer)

[styleruk]

Now I've read a few threads here but they don't quite cover what I need.
Leaving for hols in a few days so fired up the fridge and it clicked as if to expect gas..but I'm plugged into the mains!
Checked that the fridge is getting 230V mains and it is.

So it looks like it does not want to switch over to mains, I will trial when I get home tonight to see if it will fire up on 12v, but does anyone know if there is a relay that clunks over to mains that might not be working? I've noticed a 12v relay in the back, I don't think this is it as the mains does not connect to that. Quickly took the top front off and there is a potted PCB there, can't really see a relay there either.

I will investigate more tonight but thought if I asked the question now, by the time I get home from work some people might have suggested a few things I could try.

Cheers.
Simon

 

[denisejoe]

didn't read properly

Joe

 

[styleruk]

eh?

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[DavidG58]

If you manually switch to mains does it work off mains correctly then?

We have had odd quirks like this where it doesn't auto select, but move to a correct manual option, usually OK then back to AES all then OK till the next time which might be months on

 

[styleruk]

My model does not have manual option, just two buttons on the front. ON/OFF and temp

 

[DavidG58]

My model does not have manual option, just two buttons on the front. ON/OFF and temp

that I guess is progress for you

no option to use on gas if you want to if hooked up?

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[styleruk]

OK, all sorted. Worked into the evening on that one.
To answer a few questions, the fridge ran fine on gas, then when unplugged form mains it worked fine on 12v when the engine fired up. So it was just the 240v not working. This was not a big problem as all I needed to do was isolate the mains if I wanted it to run on gas. As soon as it does not get a signal from the alternator or mains, then it fires up gas, so we would always have a fridge. (we are going to scotland this week so I guess the fridge outside is as bigger fridge we'd ever need!)

On top of the fridge behind the front cover there is a large PCB (not the control PCB), this is potted (resin), to protect the board from damp. This also has a load of small black boxes, these are relays. So I very professionally tapped them all with the soft end of my screwdriver. (I'm a qualified mechanical design engineer....what do I know about electrical spikey stuff anyway).
This worked when I un-isolated all the power.

So I guess the relay just got sticky being left for a while. I would think driving the MH and the vibrations from that would have done the same. So no panic anymore, I can have ice for my G&T again.

Thank You all.

Si

 

[Lenny HB]

My have just been coincidence tapping the relay. Did you check the mains voltage? They don't like low volts and there appears to be a software bug, on AES with low mains they try to light the gas but because mains is detected the gas valve is turned off so the fridge doesn't work ignitor just keeps clicking.
When this happens it is best to select gas manually.

 

[styleruk]

Yes, I did check for 240v, first thing I did. And yes, it does try to light the gas then gives a red light if the gas is off. But as I said earlier, it does not have a manual switch over, you'd have to isolate the mains if that was the case. All past tense now as it works.
Just thought I'd update what I did in case anyone else comes across it. It's quite old so I guess the relays start to stick or break down. Eventually I would have to get a new board but by then, I would sooner buy a new fridge. That is the way of the modern world, as people cannot be trusted to do these things manually. That said, it's a good thing in other ways, I'm an automotive design engineer so I understand how stupid people are, this PCB will stop the gas firing up when you stop at a petrol station because when you turn the engine off, there is a 15m delay before the gas fires up. That avoids the light clicking and trying to light the gas whilst people around you pump highly volatile evaporating liquids. You'd only need two stupid people to meet and boom! But we are not that stupid are we!

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[DavidG58]

I would sooner buy a new fridge.

you might rethink that one if you look at the prices, we bought one a couple of years ago, long story as I bought the wrong one, but a Dometic tower with separate freezer will be £1000+ and could be £1500+, if like ours it also has the cooker attached (the bit I hadn't realised ) I dread to think how much they charge

Glad it is all working again

 

[styleruk]

Quite, but worth it if you use it. It's a very good fridge and I'm not suprised at the price. You'd pay more because of what they have to do. But I guess I'd try and fix it before it came to that.