"JAXAshby" wrote in message
...
Would be nice to know what brand that was.

Espar.

Mine
draws 17A while starting (maybe a minute) and 5-7A while running.

that is one hell of a lot of amps overnight. Even a much greater bunch of
amps
if you don't move the next day.

Not really, it only runs maybe 10 minutes every hour. 20-30 AH per day for
heating is not too bad. Not sure what moving has to do with anything unless
you mean moving towards a warmer climate.
..
btw, you might wish to actually measure just how many amps your system
*really*
burns. That brand new system on the boat would run out the about 50 to
60 amp
capacity of the brand new Group 25 in less than about 5 hours. (note a
Grp 27
rated in about 105 amps, gives up about half that before it is effectively
dead. That is the way battery ratings work.)

I know. Such a small battery is not suitable for any forced air heating
system. Perhaps a Force 10 or Dickinson would be a choice for a boat
that does not support a serious battery bank.