These heaters (called "bus heaters" around here) are great, but only if you're motoring. I wouldn't rip it out. One day you'll be glad you have it.
I'd hesitate to run the main just for heat or hot water
, although in a pinch I've done it. For that you're better off with a generator
Better still would be a diesel-fired hydronic heating
system which can heat both the potable water and the cabin
. Down side is where to put the baseboard heaters, not to mention the cost. For now my forced air diesel
heater works pretty well, but one of these days I'd like to add a bus heater. Let me know if you do decide to remove it!