John, Do you have any pictures and or discriptions of your M15 installation? Thanks Doug Kelch M310G "Seas the Day" --- On Wed, 6/10/09, John R. Butler <theoldcat@cox.net> wrote: From: John R. Butler <theoldcat@cox.net> Subject: M_Boats: cabin heaters To: "Boats Montgomery" <montgomery_boats@mailman.xmission.com> Date: Wednesday, June 10, 2009, 10:09 AM     I have had successful cabin heaters on a Cape Dory Typhoon, a Cape Cod Catboat, and now my M15.  I always had a good Charlie Noble for each, and I believe that using an external combustion air source is counterproductive to one of the benefits of cabin heat: Any vented, internal combustion heater lowers the relative humidity in the cabin by raising the cabin temperature.     I used natural oak charcoal for fuel on the first two, and Sterno "canned heat" on my current heater which had to be built smaller for the smaller cabin size.     Solar powered cabin ventilation provide more than enough combustion air.    John R. Butler theoldcat@cox.net First M15 was "Joy", '83 #264 Now sail "Rejoyce!", '86 #361 _______________________________________________ http://mailman.xmission.com/cgi-bin/mailman/listinfo/montgomery_boats Remember, there is no privacy on the Internet!