more furnace questions
(A good subtitle for this reply might be: "the more you know the less you are sure of")
Seattle Boat Show was
very lightly attended... not good for the (surviving) brokers but nice to be able to spend some time with the vendors.
Had a lengthly talk with the reps for Webasto, Espar, and Wallas.
The good news is that, in a niche market like ours, no one totally insults the other brand
or rep.
There are, however, some interesting design differences... The major one I am now more aware of is that the first two are "turbine" style designs with all motor/fan functions on a common shaft, and the the Wallas quite different, with the circulation and heating components separate. Also, the Wallas uses an entirely different run cycle. The Webasto and Espar, if I recall correctly, power up and run on demand, and therefore do run their startup and shutdown cycle whenever the thermostat calls for more heat. They use no power when "off".
The Wallas goes thru its startup cycle and ramps up the burner use and the circulation fan upon demand and then reduces down to a "pilot light" (my words) standby mode with the burner chamber remaining hot and using a trickle of diesel and power until the thermostat calls for a quick ramping up to heat the boat again. It goes thru a complete shutdown cycle only when you tell it to do so.
The gist of the info is that neither uses significantly more or less power/fuel, but do their work differently. Also, the Wallas rep claims that theirs is intrinsically very quiet because it uses a separate circulation fan that is not tied to the burner function and is virtually noiseless inside or outside the boat.
The Webasto guy, when quizzed about outside noise, will sell an ss mufler for an additional $100.
For our size of boat interior, we would probably be shopping a Wallas Nautic 40D model, or a Webasto Air Top 3500ST, or an Espar Airtronic D4.
If anyone else has some input on these, especially the Wallas, please do chime in! Around here the most common model I see on nearby boats is the Webasto. There are some Espars, but the ones I hear about are older models. Webasto has the most retail outlets by far... including "discount" vendors in my fair city. FWIW, most of the ones I am aware of on other boats are quite noisy from outside, altho not too noticeable when you are inside.
Regards,
Loren
