Source of inlet air supply for Webasto/Planar

[idratherbeboating]

Hi -

I'm in the process of planning out the ducting for adding heat (Webasto/Planar) to my RT29 and came upon a quandary... what's the best source of input air supply?

Obviously I want to duct the heated air into the berths, etc. but where should the source air for the furnace come from?

Some options:
-cabin
-bilge
-outside
-no ducting (it sounds like factory install just pulls the air from whatever cabinet/locker the unit is located in, with no inlet air ducting)

Curious how folks are set up and how it works for them... Please share!

Thanks,
Austin

 

[Irish Mist]

When I installed my Panar heater on my 2011 I installed it below the engine vent in the storage starboard side in the cockpit.
It gets combustion and makeup air from the engine vent. I wanted to pressurize the cabin. ( I have seen a makeup air vent from the cave if you want to do it that way.)
In my 29 I had a straight run from this location for the heat pipe to behind the kitchen cabinets. I put an outlet pointing into the cave, one forward under the helm step for the main cabin, one in the bottom step into the berth.. The boat is very well heated with this arrangement.... except the head. I didn’t want to add a hole there because of the shower. I have a small 200 watt electric heater I leave on in there when on shore power. If the head door is left open that works too if at anchor. We have the cockpit closed in and I am contemplating adding an outlet in the side of the step for the cockpit.
The exhaust goes out the starboard side.. I was trying to get the exhaust out the stern so on a side tie or rafting to another boat it would not be an issue.. This was too hard to do so it’s out the side and usually not an issue I can’t work around.. One fender didn’t fare well though 🙂

 

[Gin]

Hi Austin,

You are right about how the factory seems to do the installations. On my R27, there was an intake grate right under the port side passenger seat step that took in air from the cabin. On my R37, the heater unit is basically under the helm seat and draws from the large volume of air under there, which is interior air from the large area under the helm, the starboard cabinets, and the starboard bilge. As I understand it from the materials I’ve reviewed, the benefit to pulling the heater air in from inside the boat rather than from outside, especially, in cold winter temps, gives the heater warmer air to work with, which makes it more efficient.

If that approach appeals to you, maybe other R29 owners can weigh in to tell you more specifically where there heater is mounted and where the intake draws from. You can then duplicate that.

Oh, on combustion air intake, I’m not sure how that was done on my R27. On my R31, there is no combustion intake hose, just the open intake pipe. So it draws directly from the air surrounding the heater, same as the main air intake.

Good luck with your install!

Gini

 

[knotflying]

On my R-27 I installed the Webasto after market. The heater is located behind my stove. Instead of a hole through the hull for combustion air I ran the intake hose back to the gunnel and put a screen on the end to prevent critters from getting in it. The cabin air intake is in the cabin. Similar to a house system. Why not take warmer air in to warm rather than cold air.

 

[Ralf H]

Hi Austin,

Lots of good answers here, but just to be sure, it all depends on where you will mount the unit itself. As long as the unit can draw enough air from the surrounding area, that will be the first criterion. Once you have decided on that, just make sure that area has the ability to get air if it is in an enclosed area. This can be easily done, just as we do it, by installing an intake vent in the most convenient area to allow it to accept return air. If you have done that, you should be fine. Hope this helps, but let us know if you have any additional questions.

Thanks!

Ralf