We have the Truma blown-air heating in our caravan, which has performed really well during cold-weather touring; however, the washroom at the rear never gets warm - with the pipe-run to the washroom being the longest and also being routed outside and underneath the van, it is not surprising. It seems that loads of other people have lagged the external pipe, so I thought I'd have a go.
Before: The factory "insulated" pipe.
I purchased some pipe insulation in the form of Armaflex 80mmID x 13mm Wall - This came as a 2 metre length which was perfect, with no wastage. There is a thicker option, but i'm glad I got the thinner walled version, as the pipe was routed close to the chassis rail, so required some massaging to fully encompass the pipe. Another wrinkle was the grey water drain pipes, which ran parallel - I unscrewed the mounting to allow some flex whilst i worked.
Pipes in the way.
I purchased some 200mm x 4.8mm zip ties for securing the insulation but they were too short. Luckily I had just enough to double-zip them, so I burnt through all 50 purchased for the job, plus some more I had in the garage. Buy 450mm+ if you want to do this yourself.
Overall the job is not perfect, but has insulated over 95% of the pipe so I hope tto have at least some warm air getting to the washroom!
Finished job
Loads of zip ties
Before: The factory "insulated" pipe.
I purchased some pipe insulation in the form of Armaflex 80mmID x 13mm Wall - This came as a 2 metre length which was perfect, with no wastage. There is a thicker option, but i'm glad I got the thinner walled version, as the pipe was routed close to the chassis rail, so required some massaging to fully encompass the pipe. Another wrinkle was the grey water drain pipes, which ran parallel - I unscrewed the mounting to allow some flex whilst i worked.
Pipes in the way.
I purchased some 200mm x 4.8mm zip ties for securing the insulation but they were too short. Luckily I had just enough to double-zip them, so I burnt through all 50 purchased for the job, plus some more I had in the garage. Buy 450mm+ if you want to do this yourself.
Overall the job is not perfect, but has insulated over 95% of the pipe so I hope tto have at least some warm air getting to the washroom!
Finished job
Loads of zip ties