Heater question

[Mr. Fixit]

Defender sells a heater that uses engine coolent for auxilary heat. My engine has the outlets/inlet installed that would accept this type of heater. Does anybody out there use this type of heater?? I realize that this would only be auxiliary heat available when the engine is running. They are listed at 28,000 btu. I have heated my boat with a 1,500 watt electric heater in marginal conditions. I expect to spend the summer early fall on the Hudson River/Canal system and am wondering if this type of heater would be worth it. I have room for the fan/grill assembly very close to the engine. Any imput would be appreciated. I am still working on my primary heating system. When I changed interior i did not allow room for heater. Highlights need to plan well before changing things. BEST LAID PLANS OF MICE AND MEN----

[AdriftAtSea]

Yes, I've used a hydronic type heater.  They're very effective, especially if you're doing something like motoring down the ICW in the middle of December when it is only 23˚ out... which I did last month.