Hydrotherm has provided innovative solutions for the ever changing comfort needs of both residential and commercial boiler applications. Hydrotherm pioneered the modular boiler concept which provides maximum efficiency and flexibility in commercial applications. These 300 BTUH modules eliminate the energy-wasting "all on/all off" firing sequence of single-input boilers by step firing to match heating demand. Our cast iron Multi-Temp modules or higher efficiency Multi-Pulse modules can be configured to meet the load requirements of any home building or institutional application.