Boilers are used in both hot water heating systems and steam heating systems. The hot water heating systems most often encountered in HVAC work will be low temperature systems with boiler water temperatures generally in the range of 170-200 degrees Fahrenheit. Most of the steam heating systems will use low pressure steam, operating at 15 psig Learn More
Hot water boilers (i.e., not generating steam) combusting gaseous, liquid, or biomass fuel with a heat input capacity of less than 1.6 million Btu per hour are included in this definition. The 120 U.S. gallon capacity threshold to be considered a hot water heater is independent of the 1.6 million Btu per hour heat input capacity threshold for Learn More