Since Island Eagle is berthed in a location which is cold and damp, and will be used in a location which is cold and damp, and may one day find herself in Arctic waters, a good heating system is a a necessity. There are a few challenges though. First is the sheer size of the boat. A single central stove or wood heater would not do the job at all. And 60 feet translates to about 6500 cubic feet of volume, by my rough calculation. 60 feet is a long distance to have to run the ducts in a hot air system, so we figured that some type of hydronic (hot water + radiator) system would be the best.
After investigating a number of possible solutions, we settled on a 65,000 BTU Hurricane heater. This is a compact direct-vent diesel-fired heater which heats water, which in turn is circulated out to individual radiators. In addition, an additional loop allows the use of the Hurricane to heat the domestic hot water (DHW) tank. After some debate we decided to install the heater in the engine room, over the port diesel tank.
When the hot water comes out of the heater, it enters the manifold on the right and then flows out to four individual loops (forward, midships, aft, and DHW). Returning (cooler) water enters the manifold on the left, and is then pumped back to the heater (through an expansion tank, located in the pilothouse settee).
The whole thing is controlled by a small computer. The operation is pretty clever, and works like this: Each cabin is equipped with a small radiator and attached fan. Each cabin also has a thermostat. When the thermostat calls for heat, two things happen: The fan on the appropriate radiator is started, and the pump runs. The actual heater then monitors the temperature of the water, and when that falls below 170 degrees, the heater kicks in and heats the water back up to 180 degrees.
The final little treat is a heated towel rack for the master head. This is simply towel rack made of hollow tubing through the hot water is run. There's nothing like stepping out of the shower and grabbing a nice warm towel, and plus it even saves on washing because wet towels dry in an hour or so instead of getting musty.