Rinnai Q Series wall-hung boilers offer a fully modulating pump coupled with a stainless-steel heat exchanger. With Btu inputs ranging from 85,000 to 205,000, it is for any home or light-commercial applications in need of zone heating that has a separate hot-water source. The exception to the series is the 175,000-Btu Q Combi Boiler, which provides both heating and domestic hot water. All Q Series Boilers are approved for venting lengths up to 200’ and comply with the SCAQMD low NOx requirements.