Fridge working but not cooling

Happy Jim

Happy Jim

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Finally managed to get away for the weekend and the fridge & freezer are not playing!

It's a Dometic RMD8505 AES from 2010, "working" on 12V (driving), and 240V or Gas when parked, nice blue light (no red light alarm). I've got heat coming out of the top vent happily but the fridge and freezer are doing nothing (5 hrs driving, parked up on site for 10 hrs).

Any thoughts gratefully received!

I do have some tools with me and am reasonably DIY capable.

Warm beer though - 👎

Thanks
 
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I had on mains from 2pm till 7 pm, gas from 7 till midnight - zero difference (both pushing heat out of the top vent, but no cooling at a in either fridge or freezer)
 
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Not that I've noticed but will whip the cover off in the morning and have a sniff around

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10 years old, been standing for a long while, crystallisation might be blocking the circuit if none of the other valid advice strikes home. If it is that then there are some avant garde solutions like turning the unit upside down, perhaps just getting a new cooling unit, or the ultimate a new fridge!
 
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Nor getting to any level of cold at all (it's ambient with outside).

Fridge is 10 years old, but used over that period (last was a month ago when it was fine).

No covers fitted.

I've read about the invert the fridge thing before.....why would that work? (That'll be a Monday job when I'm home though if I go down that path)

Is there a way to test the thermocouple? (I have a multimeter with me)

Many thanks

Jim

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Oops double post, sorry!

Van is spot on level as well
 
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Happy Jim said:
Nor getting to any level of cold at all (it's ambient with outside).

Fridge is 10 years old, but used over that period (last was a month ago when it was fine).

No covers fitted.

I've read about the invert the fridge thing before.....why would that work? (That'll be a Monday job when I'm home though if I go down that path)

Is there a way to test the thermocouple? (I have a multimeter with me)

Many thanks

Jim
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Won’t be the thermocouple if the flame is staying alight.
 
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From what the OP has described it would appear that there could well be a blockage in the cooling unit, which manifests itself when on mains electric as the system is not powerful enough to circulate the coolant/blockage, but it is when switched over to gas, though in time it will stop working on gas.

Pete
 
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Happy Jim said:
I've read about the invert the fridge thing before.....why would that work? (That'll be a Monday job when I'm home though if I go down that path)
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The fluid can get in the wrong part of the circuit, by inverting the fridge it gets back to the boiler, it doesn't always work, but if you have tried everything else it's worth a try.
 
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GeoffnDee said:
Is it possible that the Thermistor on the fins inside the fridge has been dislodged (or is faulty) ?
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unlikely as the OP can feel heat from the fridge vent on electric, if the thermistor was not working there would be no call for cooling, so no heat at the vent on electric.
 
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Got home from Wales at 5, fitted an inverter that arrived while I was away and set about the fridge...

Mains off, gas off.
Open freezer door, remove 2 plastic screw covers, remove 2 screws.
Ditto fridge door.
Remove lower outside vent cover.
Undo gas nut (check gas gone, pause for cup of tea (wary of gas!).
Unclipped 3 electrical connectors.
Wiggle fridge out, 1cm top inside, push bottom of fridge from outside.....repeat til nearly out!

20 mins max, much easier than I thought.

Fridge out, inverted, shaken a bit, inverted a couple more times, back the right way up now (lots of sloshing/gurgling so there's still fluid in it).

Back in the hole and all connected now.

How long should I leave it before applying power?

Cheers

Jim
 

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Happy Jim said:
Is there a way to test the thermocouple? (I have a multimeter with me)
Click to expand...

Landy Andy said:
Won’t be the thermocouple if the flame is staying alight.
Click to expand...
Same advice here as from Landy Andy. (y)

Happy Jim said:
How long should I leave it before applying power?
Click to expand...
Most instances of fridge/freezer inversion advice I have read of, is usually overnight, to give all the fluid a decent chance of draining back. Invert again, and leave it until the morning, then reinstall and reconnect.
It appears to be successful in the majority of cases...........but I'm not saying it will be in your case.

Good luck with it. (y)

Cheers,

Jock. :)
 
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MHFun chalks up another success!

I put a new battery in my Bluetooth temp sensor, 08:30 I turned on the fridge (240V), nothing happened until 10:30 and then the magic started 😀. It's on level 4 of 5 (5 being coldest) currently, and still dropping!

Looks like I owe you all some Virtual pints of thanks 😊
 

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jonasw19 said:
Oddly we find our fridges more efficient set at 2 or 3(5 being coldest)
Click to expand...

If you think about it by putting it on the higher setting the gas will stay lit for longer and will increase the ambient temperature at the rear of the fridge so it gets a bit self defeating! That's why people add fans to increase the airflow👍
 
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Happy Jim said:
MHFun chalks up another success!

I put a new battery in my Bluetooth temp sensor, 08:30 I turned on the fridge (240V), nothing happened until 10:30 and then the magic started 😀. It's on level 4 of 5 (5 being coldest) currently, and still dropping!

Looks like I owe you all some Virtual pints of thanks 😊
Click to expand...
Did you invert the F/F overnight, or didn't you bother?

Glad to see that you are sorted. (y)

Cheers,

Jock. :)

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JockandRita said:
Did you invert the F/F overnight, or didn't you bother?

Glad to see that you are sorted. (y)

Cheers,

Jock. :)
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Hi Jock,

No, had it upside down for about an hour then refitted it and left it to settle overnight.

I've taken it off 240V now (position 4 was too cold, position 2 got it around 5-7 degrees.

I've just given it a good clean and an now running it up on gas to see how it fares.

Regards
Jim
 
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Oh Arse!
Monday through Thursday and all was good on both gas and 240V, shifted the van Thursday eve in prep for leaving on Friday morning (Festival time).....lost all cooling again.

Got to site at 11 and gave it a couple of hours (I'm level), still no cooling.
Whipped it out and gave it a good shake/invert etc....still nothing.
Mate with me is a gas man so flue off checked spinney thing all clean, burner out all clean and good flame.

Anyone know what resistance the thermistor should be at ambient (23c)? Mine registered 9.8KOhms.

Not relishing the thought of buying a new fridge.....so If anyone knows of a good RMD8505.....I'm yer man 😉

Thanks
Jim
 
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The cooling unit has likely failed, relatively confirmed by the inversion remedy I suggested delivering a respite to failure. A new cooling unit is quite expensive and the financial logic, unless you have access to a caravan kit breakers with a used cooling unit, is to simply replace the fridge.
 
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If you can try disconnecting the thermistor and set the temperature to coldest setting and see if that improves things.
If it helps the values for RM8xxx are 20c = 12.11 kOhm 25c = 10.00 kOhm
 
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