webasto again

[dpiano]

The furnace on our 29 ranger has conked out again. Sure marine in Seattle replaced the drive motor last march. They also replaced the hot and cold sensors and the evo control. Back then, the furnace would shut down and give an overheat code. However when I sent the furnace up to them they ran it for hours on the bench without overheating, before they did the repairs. After that it ran ok during the spring but then of course the furnace was not used through summer. Now the furnace is shutting down and giving an 08 code, which indicates a bad motor. Sure marine met us at shilshole last week, did a reset and furnace started. He is saying the heat duct was installed wrong by Ranger; it should not have a 90 degree bend coming out of the furnace causing it to run too hot. After the tech left, the furnace shut down again. I called Webasto and their tech said that the bend shouldn’t cause a problem. I remove the furnace again and sent it to Sure Marine. They started it on the bench and it ran fine all day. They are very helpful, going to replace the drive motor again, 2 days before the 6 month warranty expired on the second motor even though they are not sure why we are having trouble. Last march Sure was saying there was possibly a restriction in the hot duct. I pulled the fridge, crawled in and saw no kinks in the duct.
Anyone have any good ideas about this?
If we keep having problems I may want to rip out the webasto and put in something else. I read somewhere on this site somene replaced the webasto with a Planar. It’s made in Russia, but on the web it looks suspiciously like a webasto. This sure is discouraging!

 

[Salty7]

I'm sorry to hear your Webasto problems continue. I wrote about the Planar and assure you it is not a Webasto. They look the same but the Planar I owned worked far better than the Webasto I replaced. Be careful if you go the Planar route, you want the real Russian Planar which seems currently to be distributed by a business in Canada. There is a Chinese knock-off on Amazon and it is definitely not the Russian Planar and I know nothing about how that product is made or supported.

 

[NorthernFocus]

I can't even guess how many hours we have on the Webasto over ten years of use in Alaska. Since installing it myself all I've ever done is clean the fan a couple of times during spring commissioning. If there is in fact a 90 degree fitting right at the outlet that could certainly be the problem. That will reduce flow through it which in turn makes it run hotter. That also seems consistent with the bench test that Sure Marine did.

 

[Salty7]

I 2nd what Dan is saying. If there is restriction, which a 90 will definitely cause, that will make the furnace run hot. The Webasto I had to replace slowly grew it's heat exchanger (through expansion) from running hot, that in turn made the motor bind slightly and eventually burn out.