20-Gallon Water Heater without Heat Exchanger - 240V
A marine water heater is simply a small, insulated tank downstream of the pump. You must have a pressurized water system to operate a water heater. The pump draws water from the storage tank(s) and fills the water heater tank. Inside the water heater is an electrical heating element and usually a coiled tube called a heat exchanger. When AC power is available, the electrical element (controlled by a thermostat) heats the water. Away from the dock, the hot engine coolant is routed through the coiled tube to heat the water in the tank when the engine is running.
Water heaters have four threaded ports. The tank inlet connects via a tee connector to the outlet hose from the pump. A check valve is required in this line or in the heater to prevent hot water from migrating back toward the pump. The outlet connection supplies heated water to the hot side of all faucets, also using tee connectors. The other two ports are for the heat exchanger connection, which varies depending on engine installation. Use only metal fittings to plumb a water heater, never plastic. If a pressure-release valve isn’t integral, the heater will have a fifth port for this essential component.
Raritan’s 1700 Series Water Heaters are built for the long haul. A glass-lined steel tank and a rust-proof jacket keep the Raritan water heater looking great and lasting for many years. Research has shown that glass-lined steel tanks are more durable than tanks made from just stainless steel. To increase longevity and fluctuations in water quality, Raritan includes a sacrificial magnesium anode that ensures a long tank life.