Wabatso Thermo 90 Hydronic System

[Flyboy01]

I purchased a Thermo 90 hydronic unit and am just beginning the install on a B-423. I have a number of questions regarding heat exchanger size/locations, method for tying back into boat's domestic water heater, is a separate calorifier necessary etc.? Also, is a Sure Marine Water control panel worth the investment at $550 USD or is there a more efficient way to tie on the thermostats/zones?

Thanks,
Steve

[Lepke]

My boat had a boiler and baseboard type radiators when I bought it. I switched to marine (bus type) heaters. The radiators required a higher set temp and took almost 10x longer to heat a cold boat in 40°F. Insulating the lines saves a lot of diesel. Diesel was $4/gallon then.
I can tell you how to set up zones with normal heating components, sensors, valves, stats, etc., but a little complicated for a reply. It may be easier to use their control panel.
In the end you want the circulation pump to come on when heat is called for in a zone. If you use blowers, you want them to wait until the hot water arrives before coming on - so no cold air blast. Also it's better to only circulate thru the least main line pipe, so other valves cut off parts of your main loop.
I can also heat the boiler water from a pellet stove coil and the main engines coolant, so don't use the water for domestic. And the boiler runs at 15psi. and the fw at about 40.