Air heater
More than one year ago I bought a new complete Webasto air heater set for my 411 and I finally plan to install it. The 411 is already prepared to have one and, in fact, there are many signs of a preexisting system. Namely there is an outdated electronic unit under the navigator seat, a thermostat above it, a lot of wiring and a small copper tubing running from the diesel pre-filter to the kitchen cabinets where there is a pump, and then along the port side to the aft bulkhead and crossing again to the starboard side. Apparently the old Webasto unit was placed somewhere on the starboard side under/behind the engine throttle lever. Discussing the matter with other Swan friends, I have almost decided that the best place where to put the main unit would not be the original place but under the starboard aft bunk; the reason is better protection from humidity. I am ready to accept advices also on this but my big doubts regard 1) diesel line: shall I reroute the line all the way along the starboard side from the pre-filter directly to the aft bunk or it would be more convenient to use the old design, re-entering from the back? 2) exhaust: I cannot find signs of where it was. Which is the safest place to drill its way out? 3) burner air intake: is it sufficiently safe to get air from the rudder/autopilot room behind the aft bulkhead? I understand that there may be some possibility of smell or combusted gas leak from it.
I would very much appreciate advices on all those question and please notice that 411 is just indicative: all our boats from 36 to 48 are very similar (and great!)

Daniele 411/004 Luna Menguante

Dear Daniele,

In my 41 there was originally also a Webasto heater, mounted under the small piece of deck behind the helmsman's seat. There was also the exhaust. When I bought the boat it was already gone and there was a Eberspacher mounted underneath the floorboard of the small passage to the rudder. I use an Eberspacher D5air, a bigger one doesn't fit there. But it is strong enough. I also found the original fuel line coming from the filter wich leads on the starboardside to the rear bunk (with pump). The exhaust is now mounted near the stern, a few inches under deck level. Picture 41/030. For the intake air for the burner I use one of the vents on the aft deck. To prevent smell and lack of fresh air for the burner and myself. The heated air is recycled. The thermostat is still located above the navigator's seat and is doing quite fine there. I also made an extra outlet in the bathroom. Nice when it's freezing outside!

Maurice 41/030

Thank you very much Maurice, your indications are of great help. If I understand well your heating unit is fixed on the ceiling of the rudder room which, I reckon, has a lot of available space. If so, do you have any advice of how to fix it? Indeed, placing the unit there would be more convenient for both the exhaust and the burner air intake lines. I am also worried about the final part of the exhaust line: did you devise something to prevent sea water input or condensation formation?
Daniel

Dear Daniel,

I guess the 411 has more space in the rudderstock room than the 41. With the installation kit you should be able to mount it. As the exhaust concerns, just near the heaterunit there is a little hole in the exhaust pipe with a copper tube curly shaped attached. It is filled with a little bit of water to prevent exit of gases but when there is water in the exhaust it comes dripping out. Of course, when a wave comes in , it will never do. It is just for condensation drain.

As I mentioned earlier, the exhaust outlet is mounted high on the hull near deck-level. As far as I know, there is no water coming in. I have also bend the exhaust pipe as high as possible like a Swan's neck. An other issue on the exhaust outlet to keep in mind is placing a cap on it. I once had a strange smell coming from it and I found out that there were a few spiders nests in it!

Best regards,

Maurice

Daniele,

there was also a Webasto heater on our 41/022 which crumbled to rust when we bought it some 25 years ago. It was installed behind the helman's seat under the deck using bent stainless steel battens fixed to the deck (stratif.) as explained by Maurice. For the exhaust there was a stainless steel chimney screwed on a threaded outlet itself fixed through the deck. When not in use the chimney was taken off and a threaded cap closed the exhaust's hole.

We have dismantled the lot, but kept the chimney, the outlet and the cap (80 to 100mm diameter).

So if you are interested I can send you pictures (but not before 25 may) and the lot later. But I wonder if new heaters have not much smaller outlets/chimneys??

Kind regards. Philippe. 41/022

Philippe,

thank you very much for your input. I confirm that the present exhaust pipe is much smaller, something between 20 and 30mm diameter.
For this reason it does not need any more a bulky assembly and, usually, is fitted either aft or on the side of the boat well above the water line.
What still worries me is the possibility of water/humidity accumulating in the pipe and of heat charring the surrounding fiberglass.

Regards
Daniel