14' Series Dometic fridge playing up

Boots in Action

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Mar 13, 2017
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Sorry you think that Mike, you both tend to rabbit on and the original question tends to get buried before a few simple questions get answered..... I'll just leave it to you to sort out in future...............
Carefully crafted questions laid out in a step by step process will always prove to be the best way to get the proper answers, avoids time wasting and eliminates a plethora of "unknowns", guess work and confusion. And explanations of how, why and when helps those looking for the correct answers. If that is "rabbiting on", then so be it!
 

Boots in Action

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Yes Ted @Ted farkas, @mikerezny mentioned that earlier. It is only when you get into the operation of absorption fridges that incorrect operation problems are explained fully. You are not the first person to fall into that trap, but there are several posts on this earlier. That is why the video on absorption fridges is so important as it brings up the pitfalls of improper operation long term. When this conversation first came up, I was able to source several items of value to members, including that one regarding the slow build up of sodium chromate crystals - not evident at first - but finally catches up and blocks the percolator tube in boiler. Speed of blockage all depends on how far off level, how long and how hot the boiler gets when water/ammonia mixture is not moving. There is another site too on how this happens in greater detail, which I will send to you when I find it again. Happy travels.
Hi Ted @Ted farkas , here is a link for you to read regarding the problems caused by not having a van level when operating. This follows on from what I said earlier and applies to both Dometic and Thetford (Norcold) absorption refrigerators. Pity you did not know about it earlier.

 
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Boots in Action

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Hi guys
Thanks for the replys. Been using the fridges for years and aware of there nuisances. However never read anywhere that using unlevel may cause damage, I like many others just assumed it would be inefficent only. I reckon it's a block somewhere....I'm on the road so hopefully it'll rattle loose and I'm gonna tap the small tubes..... learnt a lot about absorption fridges in the last 2 hours.... thought they were basic

Cheers ted
More info on what happens to your absorption fridge if you operate (or try to) when not level. This link also advertisers a piece of equipment to prevent this happening if you are not prepared to make sure fridge is level, but may not suit most. The informative part is what happens in the boiler section, and if the sodium chromate rust preventative crystallizing does not eventually block the boiler tube, then the high boiler temperature will weaken the metal housing. Remember too that the whole system is highly pressurised (at approx 300 psi). Just more info to protect your fridge.

 

Ted farkas

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$400 dollars later and checked throroughly - supposedly nothing wrong with fridge???

Once on level ground I'll check this myself. Maybe obstruction bumped loose after travel.

Regards
Ted
 

Boots in Action

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$400 dollars later and checked throroughly - supposedly nothing wrong with fridge???

Once on level ground I'll check this myself. Maybe obstruction bumped loose after travel.

Regards
Ted
Hi Ted @Ted farkas , you may have dodged a bullet in regards to potential permanent damage to your 3 way heat absorption fridge. Only time will tell if "problem" has been eliminated or just temporarily cleared. At least you now know what to look for and keep an eye on. I assume that fridge was removed from van to be tested? If so, then the rotating and inverting by fridge people may??? have got you out of trouble. Good luck and thanks for proving feedback.
 
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Ted farkas

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Hi Ted @Ted farkas , you may have dodged a bullet in regards to potential permanent damage to your 3 way heat absorption fridge. Only time will tell if "problem" has been eliminated or just temporarily cleared. At least you now know what to look for and keep an eye on. I assume that fridge was removed from van to be tested? If so, then the rotating and inverting by fridge people may??? have got you out of trouble. Good luck and thanks for proving feedback.
Nope, they just plugged it in with a sensor to track temp. I should have turned it on when I got home to see if it did shake loose which it had.

thanks
Brett
 

Boots in Action

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Nope, they just plugged it in with a sensor to track temp. I should have turned it on when I got home to see if it did shake loose which it had.

thanks
Brett
Hi @Ted farkas , great to hear your feedback and that you have "got away " without any apparent permanent damage. And now you have some idea of how absorption fridges work.
I currently have a problem with my old Finch 40L 3 way fridge which I have had for the last 10 years or so after a friend gave it to me because it kept tripping out on 240 volts. He had had it for many years from new. I have always religiously made it level when in use after I fixed it (moisture in 240v heating element). Suddenly not heating whilst on 240v, but working perfectly on gas and also 12 volt when travelling. Checked 240v thermostat operation - all okay - and then 240v element - uh oh -open circuit! After buying a new element and fitting same, fridge could not get down below 8C, even though before that easily got down to below 0C and freezing drinks. Currently trying the tipping upside down and on sides for long periods, but not having much luck. Only thing I can now think of is that the percolating heating tubes near heaters have become blocked (even partially) as shown in previous post link? and are not letting sufficient ammonia gaseous vapour get to the condenser at the top to continue to pull temperature down below 8C. The condenser at the top does get hot, but nowhere as hot as before. So further dismantling and checking to see if I can free up heating tubes. Maybe it has done its time??? Will let you know how it turns out.