"bligh" wrote in message
...
Hi, I searched for a while but found no cost comparisons. I'm looking
at the Force 10 6k btu model for an uninsulated 23' fiberglass boat
of approx 900cf. It comes in two different models. Is gas cheaper than
diesel in terms of operating costs? Also, many people said neither
fuel will dry the boat out. I don't quite understand how something can
produce heat and not dry things out but I'm sure anything's possible
these days. I'm thinking of a long trip in daily drizzle. Thanks for
your time and smooth sailing everyone.

The diesel bulkhead heaters burn approximately 1 gallon of fuel in 24 hours.
Offhand I don't recall the consumption rate for propane but I'm sure Force
10 or Dickenson can provide you with this information. In a small boat
propane may be economical and its much easier to use than a diesel heater.
The diesel heaters need to be run at a fairly wide open setting to prevent
soot build-up. With a 6000BTU heater running full bore in a 23 footer you
will be very warm.
A propane unit has the advantage of almost infinite heat setting although if
you turn it down too low it might be blown out by a backdraft. I believe
they have an automatic gas shutoff feature in case this happens. Propane
units also require a vent stack that is only 1 inch in diameter vs the 3
inch diesel exhaust (you need to cut a 5 inch hole in your cabin top for
this stack so that 1 inch of clearance is on all sides). All in all I like
propane but I think it tends to be fairly expensive for long term heating.
For daysailing its more reasonable.

As for not drying the boat out, if you warm the air in the boat it will hold
additional moisture and therefore remove dampness. As this air goes into
the unit as combustion air and out the stack it will take moisture with it.
If you had the combustion gas entering the cabin this would introduce
moisture but I can't imagine anyone doing this with any reasonably large
heater. Its a good way to poison yourself, especially with a coal/charcoal
burner as these produce large amounts of carbon monoxide. Warm air leaking
out of the boat will also take out moisture. Cold air entering the boat
will bring in some moisture but on balance you should dry things out. It
may take a while depending on how wet everything is.

One thing I have noticed while living on my boat in cold weather: even with
my thermometer registering a reasonably warm air temperature it often feels
chilly. I think this is because the hull, cabin top and other surfaces
remain cold. Heat radiates from a warm body (yours) to a cold body (the
hull) and consequently you feel chilled. Fortunately a sweater (cardigan to
the UK folks) solves this problem.