Isotherm Fridge Problems

Have you had the gas checked?

Maybe it just needs a re-gas.

You have a 2 year warranty. Ring Webasto. Might just be the thermostat which has been an issue with quite a few. Had ours replaced but not for the same reason you are experiencing.

We had the same problem with our fridge in a brand new BT.
We called Stuart from BTI, took the van in and they replaced the thermostat.
Since the then, not a problem and wouldn’t change for any other product.
Cheers,
Marinus

We have had similar problems with 20 month old van. First major trip last year, fridge started to warm after a week in hotter climate. After major diversion to have it looked at by webasto service centre at Kunda Park, problem identified as crimped gas line. It has worked fine since on shorter trips in cooler climates.

On this year's major trip north, fridge lasted 3 weeks before it couldn't cool. In middle of major diversion to Adelaide webasto service centre. Fridge has been pulled out and currently being tested. No improvement seen with a replacement thermostat. Certainly hope testing doesn't take 3 weeks. Will keep fingers crossed that a solution is found quickly.

Will let you know how we go.

John

The last time it was tested they claimed the gas and thermostat were ok although low gas is what it looks like to me as the fridge takes a long time to pull the temperature down even in the freezer.
The problem is that as there are no vents on the rear of the van for inspection, the fridge has to be completely pulled out to check anything.
We should be in Broome by Monday and I can see if they have a service agent there.

J & H
Webasto do not have a service agent in Broome as such but Webasto were very happy to use the following fellow who attended to ours under warranty.
Andrew Johnstone .. 0423642856
Very nice chap.

Hi John and Helen,
We had exactly the same problem with our January 2016 17 foot bushtracker. The problem is lack of ventilation as the small vent from the fridge cavity vents into the pantry cupboard and as there is no vent to let that hot air out it just heats up the inside of the pantry. What i did was remove the very small vent that went from the fridge cavity into the pantry cupboard and replaced it with a 300x300 mil aluminium vent i also fitted the same size vent into the pantry cupboard door. In the cupboard door below the panty that opens onto the floor i fitted a 300x150 vent this allows fresh air to be vented Into the fridge cavity, there is round holes in the top of that row of cupboards for that purpose. Above the fridge i drilled 13mil holes around 10mil apart for the width of the fridge and then with a small saw cut these out to form a 13mil slot i then fitted 20mil aluminium angle mitered at the ends to form a architrave around the slot. If you do this be carefull as in the pantry cupboard corner the 240 volt wires for the fridge power point go down that corner and you cant see them by looking through the vent hole in the pantry cupboard into the fridge cavity. This might sound like a lot of work, it probably takes around a day, the vent above the fridge is quite fidderly as there isn't a lot of room to work. As i said fidderly but really worth it our fridge works great now. Before soon as the temperature reached around 30 the fridge would run all the time we found we were having to use the generator to top up our 300amp lithium battery. Now the fridge runs perfectly no matter what the temperature. All the vents can be purchased at Bunnings.
All the best Rob and Shirley Reynolds

Thanks for all the replys, it appears to be getting worse so I will try to find someone in Broome tomorrow.

Hi
I have a marine version of the isotherm. It requires adequate ventilation all around the appliance (see the installation instructions). Also, it is best to have the fridge full and even, in very hot weather, place plastic bottles eg Coke, full of frozen water, in the fridge. Free air space in a fridge results in poor efficiency.

Finally had some success with the fridge, the fridge mechanic in Broome found two problems, the first being the fan on the condenser had dropped off and was lying in the bottom, however he claimed that the main problem was that the design of the ventilation behind the fridge was like putting a blanket over your car radiator and then wondering why it overheats.
The last time I had it in for the same problem the fridgy said the same thing so I put a fan in the ensuite to help pull the air out however the new guy showed me why that was never going to work.
The current design is five 80mm holes drilled in the rear of the fridge floor and two 90mm holes covered by grilles at the top.
The fridge when pushed into place covers 50% of the holes and as the condenser pulls air from under the fridge towards the back, the cooling air has to come through a tiny grille under the fridge, up through the holes in the floor, over the hot compressor towards the front of the fridge and then do a u turn through the condenser and out the back through the vents at the top which is very inefficient even with my fan helping.
He suggested cutting a hole in the floor under the fridge, in front of the condenser and adding two fans in the door under the fridge to push air through and it has made a huge difference.
He said that once the fridge was removed and bench tested even in 30+ deg heat it worked perfectly.
In the following week I still noticed that the temperature was unstable although far better than it was and after reading a few posts regarding internal circulating fans I cable tied a 90mm fan to a plastic basket in the top rear of the fridge blowing down the ice covered back of the fridge, dropped the thermostat back to 4 and I still got to 3.5 deg, best I have seen in more than a year and that is with 33 deg outside.
When I get home I will tidy it all up and I hope to be in business.
After all this, Stuart from Bushtracker told me they are looking at ways to improve the ventilation in the rear mount fridges although I don’t know how this will help all the existing customers like me who will be out of pocket to have it fixed and the time and expense to have other people look at it, as Bushtracker fob off all warranty issues to the manufacturer. The repairs and modifications cost me $450 that I shouldn’t have to be paying.
When picking the fridge up from Kiss Refrigeration, and despite the condenser fan having fallen off and the fridge removal, replacement and testing should have been on warranty, he refused to claim and told me to try getting it out of Webasco myself as he wouldn't waste his time with them.

This problem with poorly designed fridge installation goes back a long way.
Our first BT in 2000 had fridge problems, never cool enough, running too frequently etc.
After fiddling around with a couple of remote reading thermometers it soon became obvious that ventilation was the issue.

The fridge was vented by 2 louvred vents, one located at the top of the fridge and one lower down.
Problem was that the lower vent was located above the level of the compressor unit.
This allowed the hot air to pool around the compressor and condenser and affect the performance of the fridge.

We were in Broome when things got so bad that Idecided to test my theory.
I removed the fridge and with a hole saw bored a series of holes in the rear of the “floor” where the fridge stood and another series of large holes in the rear of the shelf above the fridge.
The louvred vents to the outside where then sealed
This resulted in a good natural convection flow up the rear of the fridge.
It also prevented dust entry via the vents.

The fridge operated perfectly for the next 3 years until we sold it.
My solution was reported to some bloke at the factory who abused me at length telling me that the fridge would blow up and give him a bad name.

My second van was constructed with internal venting and the fridge has operated without fault.

There is a lot more to this story, regular snide remarks whenever I was at the factory were the least of it.
On one visit to the factory I put a thermometer down the fridge vent of a another van that was parked next to mine with the fridge operating and one at the rear of my fridge.
My fridge was 6 degrees c lower than the factory standard installation.
This result was shown to you know who.
The result, well I have not been back to the factory since and doubt that I ever will

Good luck with your fridge, give it as much air flow as possible and you will be fine.

And a PS.
The installation method used by BT is in direct conflict with the manufactures requirement.

Regards
Bob