At what altitude is an altitude gauge required on a hot water supply boiler?

An altitude gauge is required on a hot water supply boiler when the system is installed above a certain elevation, which in this case is 20 feet. This requirement is in place to ensure proper monitoring and maintenance of water levels in the system. At altitudes above 20 feet, the potential for pressure differences and issues related to water column height becomes more pronounced, making it essential to have accurate readings of the water level. This gauge helps prevent problems such as overheating, which can occur if the water level falls below safe operating limits. Monitoring the altitude ensures that the boiler operates efficiently and safely, protecting both the equipment and the facility.