The hillandale hercules 20b multi fuel boiler stove has been expertly designed to harness all available heat and use it to power home central heating and hot water systems with a heat to room output of 55kw and a heat to water output of 145kw this multi fuel boiler stove is highly efficient and effective for heating your home it features tertiary air for a cleaner burn to further enhance efficiency as well as primary air control and secondary air wash