20' Series Thetford fridge not cooling well running on gas

[Wombat6]

We have a 2016 Expanda 20.64 OB and we are now traveling in the NT where it is a bit hot. After a few days traveling on the road up from Melbourne we discovered that whilst overnight we would run the fridge on gas it was slowly warming up (we had run it on mains for a few days before we left and so it started very cold). By the time we got to Uluru it was no longer cool, even if we turned it up to max. By this time the temp was low 30’s. We then tried running it on mains when we had a powered site although, as expected, it took much longer to cool - but at least it did get acceptably cool.

We are now in Darwin and have had two techs look at it and have not been able to find the problem. My question is: are we being unreasonable to expect the fridge to cool well in now 35+ degrees? I keep thinking back to our previous van with a 20+ year old fridge which would be noticiply cool after only a couple of hours on gas. The “Thetford Agent” up hear hasn’t yet said what they will do. However, having spent a week here already we are going to have make do wiht it as it is and move on and tackle Thetford when we get back to Melbourne.

 

[Drover]

Does the bench/cupboard around your fridge get warm while it's running, if so it could be poor insulation around your fridge, they require the rear to be totally sealed from the sides and top to allow the air to flow efficiently from the lower vent thru the cooling fins and out the top vent, if allowed to get caught up and circulate around the rear or sides etc it will not run very well in hotter areas...many fit a fan to the rear to assist with this air flow and many, many folks have to insulate the rear as they are not fitted correctly, the quicker the air is moved the better.......
Being a 3 way fridge they do need to be within a half bubble of level both ways or they will not perform.

 

[Scrounger]

I spent 12 weeks in the Territory earlier this year running on gas for 9 weeks setting 4 in 35 degrees plus, yes it was working and had a good drink on gas 11 days a 9kg, My thermomitor they are all diferent showed a temp range of 4 degrees + and - 1 degree, so again on my kit it was holding +2 to +6 when about to start it might reach + 7.
It definitely cycled less at night but it would be fair to think it ran about 40 plus minutes an hour.
I did have one issue ICE build up on the cooling fins, when this happened the fridge just did not stay cold, fast defrost with spray bottle of warm water and all good.
Wife stoped putting things against fins and no more problems, but if I see more than ice cube worth if ice I now spray it away.

 

[ChrisFatboySydney]

What model fridge is it? If it is one of the newer Thetford fridge then it should have a fan switch on the control panel. That will help with ambient temps above 25-30 degrees.

 

[Crusty181]

We traveled extensively up north in long periods of 35+ without any fridge issues. Dometic 3 ways (tropical models which are all the newers ones) are rated at 40+ so you can rightfully expect the fridge to function properly in 35deg. They will struggle to maintain temp if you constantly open the door. On hot days we would take what we would reasonably need during the day and put it in the Engel, and doing that the van fridge performed flawlessly.

Our travel buddies had a Thetford and they had a few similar issues to you.

 

[Boots in Action]

We have a 2016 Expanda 20.64 OB and we are now traveling in the NT where it is a bit hot. After a few days traveling on the road up from Melbourne we discovered that whilst overnight we would run the fridge on gas it was slowly warming up (we had run it on mains for a few days before we left and so it started very cold). By the time we got to Uluru it was no longer cool, even if we turned it up to max. By this time the temp was low 30’s. We then tried running it on mains when we had a powered site although, as expected, it took much longer to cool - but at least it did get acceptably cool.

We are now in Darwin and have had two techs look at it and have not been able to find the problem. My question is: are we being unreasonable to expect the fridge to cool well in now 35+ degrees? I keep thinking back to our previous van with a 20+ year old fridge which would be noticiply cool after only a couple of hours on gas. The “Thetford Agent” up hear hasn’t yet said what they will do. However, having spent a week here already we are going to have make do wiht it as it is and move on and tackle Thetford when we get back to Melbourne.

Hi @Wombat6, once you get into the 35C range, you are on the limit on what an absorption fridge can operate successfully. @Drover has given you some good ideas, but the MAIN issue is to ensure that there is unrestricted air flow from bottom vent (AIR IN) and top vent (AIR OUT). This can be enhanced by the addition of 12 volt computer fans pulling/pushing air (even hot air!) over the fins at the back of fridge and out of the top vent. Also, inside there MUST be air movement space between all items inside fridge. A small computer fan 12 volt again ( or even the small battery operated type) does this very efficiently and similarly, if blowing across the face of cooling fins inside, reduces/eliminates the build up of ice, so no more defrosting!. And yes, no items in fridge to touch the surface of cooling fins!!!
From experience when in Cairns early last year, came across a young couple who had just purchased a second hand van and had come all the way from Sydney and were not /could not use their 3 way Dometic fridge as it could not get temp down below 11C even when on power for 48 hours. They had to use a small compressor fridge in the back of their vehicle!! Had a look for them by removing vents on van only to find that the previous owner had BOTH vents blocked off with thick carpet material and a complicated setup of little fans with thermostats to control them. Obviously put in place for protection in very dusty conditions and the thermos were not working properly, all unbeknown to new owners. Removed blocking material and as much dust from fins and pipes that we could reach, and overnight on power with vents removed, , temp was reduced to 2C with an ambient temp of 23C. This may not apply to you, but indicates just how important it is to keep back area of fridge clean and clear of any obstructions, and to make sure that there are no areas where heat can build up/be trapped and not be directed out through top vent. If you do not have fan assistance, I would recommend same for very hot conditions as it has been very successful for myself and others on this forum. See previous threads for how easy it is to do and very cheap too.
If cooling, albeit slowly on power, but not so well on gas, suggest check that gas flame is working properly as in a lot of cases, gas cools fridge down faster than 240 volt power. Just another thing to check. Good luck.

 

[Boots in Action]

Hi @Wombat6, once you get into the 35C range, you are on the limit on what an absorption fridge can operate successfully. @Drover has given you some good ideas, but the MAIN issue is to ensure that there is unrestricted air flow from bottom vent (AIR IN) and top vent (AIR OUT). This can be enhanced by the addition of 12 volt computer fans pulling/pushing air (even hot air!) over the fins at the back of fridge and out of the top vent. Also, inside there MUST be air movement space between all items inside fridge. A small computer fan 12 volt again ( or even the small battery operated type) does this very efficiently and similarly, if blowing across the face of cooling fins inside, reduces/eliminates the build up of ice, so no more defrosting!. And yes, no items in fridge to touch the surface of cooling fins!!!
From experience when in Cairns early last year, came across a young couple who had just purchased a second hand van and had come all the way from Sydney and were not /could not use their 3 way Dometic fridge as it could not get temp down below 11C even when on power for 48 hours. They had to use a small compressor fridge in the back of their vehicle!! Had a look for them by removing vents on van only to find that the previous owner had BOTH vents blocked off with thick carpet material and a complicated setup of little fans with thermostats to control them. Obviously put in place for protection in very dusty conditions and the thermos were not working properly, all unbeknown to new owners. Removed blocking material and as much dust from fins and pipes that we could reach, and overnight on power with vents removed, , temp was reduced to 2C with an ambient temp of 23C. This may not apply to you, but indicates just how important it is to keep back area of fridge clean and clear of any obstructions, and to make sure that there are no areas where heat can build up/be trapped and not be directed out through top vent. If you do not have fan assistance, I would recommend same for very hot conditions as it has been very successful for myself and others on this forum. See previous threads for how easy it is to do and very cheap too.
If cooling, albeit slowly on power, but not so well on gas, suggest check that gas flame is working properly as in a lot of cases, gas cools fridge down faster than 240 volt power. Just another thing to check. Good luck.

Hi @Wombat6 , just a quick reminder again on what may be happening with your refrigerator not working properly, something I hope you are not doing. Are you operating your fridge in proper/close to "level" operation?? A new post came up and I immediately thought of your problem. Please read some of the recent postings which may apply to your situation. If not, please just ignore and continue with your holiday. If possible, it could be your answer to your fridge not getting cold enough. Kind regards.