The next thing on the agenda was heat. We've tried offerings from many manufacturers and have settled on the Wallas 30D diesel-fired heater as an excellent choice. It's a great blend of performance-versus-price, compact size, reasonable price, quiet operation, and fuel efficiency.

It's difficult to get a photo of the installation that makes sense because the unit isn't really visible when the dinette cushions are in place. So let us explain...we're looking at the backside of the helm seat (the forward dinette seat) and the bow of the boat is to the upper left in this photo. The Wallas 30D (the metal box thing just ahead of the corrugated stainless tube) is mounted outboard of the helm seat unit under the starboard side deck. This is space that would normally be difficult to access so it makes a perfect place to install the Wallas since we don't lose usable storage space in the boat. The Wallas is a direct vent unit, the corrugated stainless tube is both the intake and exhaust for the combustion air (it's a tube within a tube). We've been running 3 vents (heat outlets) in the boat; one is under the dinette table and you can see the large black vent hose and outlet in the lower part of this photo.
Forced Air Furnace
 
The next vent is just ahead of the heater and helm seat unit and is installed in the storage box/step under the starboard sliding side door as shown here.

The large black vent tube above the step feeds heat to the vent in the forward cabin.
The vent for the forward cabin is located above the toilet on the bulkhead. We installed it there to get heat into the v-berth area without it blowing directly into one's face.
There are a couple of Wallas 30D controllers available. We've chosen the electronic controller since it monitors temperature and has some other nice features. It's mounted just aft of the helm seat on the outer starboard wall of the boat and is easily accessible from the helm seat or dinette (or center passageway since it's not a far lean across the dinette or helm seat).
E.Q. Harbor Service & Sales
265 Cornet Bay Road
Oak Harbor, WA  98277
www.eqmarine.com
(866) 679-4783