With a built in primary and secondary piping system via the internal low loss header, The FT Series floor model with smart technology pauses the heating cycle during a domestic hot water demand. It will then automatically determine if the space heating mode can be turned back on without reducing domestic hot water temperature. Since there is no diverter valve like a traditional combi unit, water is supplied for both space heating and domestic water heating simultaneously! The FT Series will continue to provide up to 3 gpm for space heating, that is plenty to continue to maintain a warm home. Simultaneous space heating and hot water all in one package. Additionally, features a high and low temperature heating demand control, domestic water recirculation on combi units and an air intake screen built into the air intake adapter.