Indirect water heaters take advantage of your boiler to produce domestic hot water efficiently. The idea is simple: hot water from the boiler flows through a coil in a water tank, thus heating the surrounding water. The boiler water and domestic water never touch or mix together.
Indirect water heaters do not have efficiency ratings of their own (they are only as efficient as the boilers they work with), but they do not require a separate energy source for domestic water heating. In most setups, the indirect tank will have priority over calls for heat. As a result, no additional BTUs are required on the boiler's rating. SupplyHouse.com offers high-quality indirect tanks from manufacturers including Weil McLain, Bradford White, Amtrol, and Triangle Tube.
