Place heating, ventilation, air conditioning and refrigeration boilers, which heats up water and circulates it through a closed radiator system to distribute heat around a structure. Connect the boiler to a source of fuel or electricity and to the circulation system. Connect it to the water supply if it features an automatic filling system. Configure the boiler.
DATA SOURCED FROM ESCO (EUROPEAN COMMISSION) & O*NET (U.S. DEPARTMENT OF LABOR)