Generic Diesel furnaces.

[prjacobs]

Hi all,
I'm looking at a cabin heater upgrade for Pagan. Right now I have an Origo 5100Heat Pal that sort of warms up the cabin. It was a $40 find at a used marine store so my investment is minimal. I also have a plug-in electric heater for dockside warmth.

But I'd like to find a source of heat that comes on with the flip of a switch or push of a button to keep the boat warm when out sailing in cold weather. My options are either a bulkhead heater or a small furnace.

I've looked at bulkhead heaters, both propane and Diesel. My favorite propane model is the Dickinson P-9000. Dickinson is a local firm with a good reputation. I also looked at one of their Diesel heaters, but after reading the installation/operation manual I'm not thrilled with the idea of fiddling with the thing every time I want a bit of warmth.

Still recovering from sticker shock after pricing a Wallas 22DT, I've been researching other options in furnaces. Webasto and Espar are a well known brands, and there are a couple of budget options too. One is the Russian-made Planar and the other the Chinese-made Snugger, both of which appear to be Webasto/Espar knock-offs.

Right now I'm still in the research stage, which may last until the warm weather, then I can procrastinate until next fall

[Bob McGovern]

Hi Peter -- our cold-weather friends know much more about this subject than I ever will (hopefully! ), but any of those options you link to should heat better & with less condensation than the Origo. Comes down to how much space you want to devote to heat (see Mads' well-executed bulkhead heater install) and what sort of heat you desire. I'm a radiant heat person myself; nothing creates a sensation of comfort better than point-source infrared bathing your face. And visible flame designs are better than television. Your bulkhead models are excellent for that. Radiant heat feels warmer than it is -- warms objects rather than air, and no reliance on convection -- so a little fuel creates a lot of warms.

Downside to radiant is that it only moves in straight lines. It won't warm the engine, or the quarterberth or V-berth, or even your own backside unless you turn like a rotisserie chicken. That was a controlling factor in designing our house, which is 80% passive solar heated. All rooms had to radiate spoke-wise from the heating hub, or the warmth would never reach them. Even then, radiant falls off as a square of distance. (Not an issue on a 30' sailboat. )

Forced air heat is the common alternative. Your Webasto/Espar diesel heater and its clones warm the air itself and can be ducted into any desired berth. Creates a different sort of warmth on the skin, can be drafty and noisy, and also generates curious relative humidity issues. Forced air heat is very dry while it is going, and because the air itself is heated, it can absorb large amounts of ambient moisture. Which is fine until you turn it off and the cabin air cools, condenses, and starts running down the walls. But for people used to whole-house comfort zone heating, forced air is a familiar experience. (I just got back from a visit at my sister's house, which is kept a steady 71*F by forced air; everyone lounges around in shorts and T-shirts and bare feet. This does not happen at our radiant house, even if the thermometer reads 80*F indoors. We also slept in the basement near the furnace, which cycled off and on about 50 times a night, making a terrible racket.)

Good Old Boat had an article detailing a PNW Ballad owner's installation of an Espar diesel heater in his boat. I can send you the article if you want it. He mentions how much effort was required to precisely balance fuel feed rate, makeup air, and exhaust drafting. Seems quite happy with the finished install. Advantage is the heater fits perfectly up inside the Ballad's high coamings, creating minimal disruption to the cabin & decks.

A third option, and this might appeal to your engineer's mind, is hot water radiant heating. It combines the efficiency, campfire feel, and reduced moisture cycling of radiant heat with the remote installation/moveable heat qualities of forced air. You can heat on demand, or keep a reservoir of hot liquid available (dedicated heater or engine-derived), also useful for domestic chores & showering. Move it around the boat in skinny, puncture-resistant PEX tubing. Add radiator units wherever heat is needed, with zone-control valves. It's quiet and needs only a very small pump to circulate. Downsides are complexity and possibly some lag time for a dedicated heater to come up to temperature. Water holds a LOT of heat.