Rheem^® ThermaForce^® Combi Boiler: No Domestic Hot Water Diverter Valve Required

July 22, 2026

Many combi boilers rely on a secondary plate heat exchanger and a 3-way diverting valve to switch between space heating and domestic hot water production. While this design is common throughout the combi boiler industry, the valve is a moving mechanical component that must continuously shift between operating modes. Over time, wear, debris, or actuator issues can affect its performance, potentially leading to service calls, reduced hot water delivery, or interrupted heating operation. The Rheem^® ThermaForce^® Combi Boiler takes a different approach. Instead of relying on a secondary plate heat exchanger and 3-way diverting valve, ThermaForce uses a patented labyrinth…