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Overview: The heat system is hydronic. A 100 gallon storage tank containing a mix of glychol and water acts as a heat sink. The water in this tank can be heated by three sources; a Kabola boiler rated at 67,000 BTU, heat exchangers that are located inside the storage tank and receive their heat from the main engines and generators, and electrical heater elements. These three heat sources can be operated simultaneously or individually. When one or more zones require heat the appropriate zone valves open and the zone circulation pump is activated. Hot water is routed to baseboard heaters and/or fan heaters. The Zones are as follow; main saloon and galley, master stateroom and head, guest stateroom and head, pilot house, forward stateroom and head, towel racks, and hot tub outlets. All zones except the towel racks and pilot house operate from thermostats. The towel racks and pilot house heat are controlled by manual switches.
Heat System Operation:
1. Underway excess heat from engine operation heats the boat.
2. While at anchor stored heat from the storage tank heats the boat for several days then the boiler adds heat as necessary.
3. On shore power the electric heater elements heat the storage tank and the boiler supplements as necessary.
Air Conditioning:
Individual Mermaid brand units are installed in each stateroom, the main saloon/galley, and the pilot house. A freshwater flush system removes the salt water from the units for off season layup.