Consequences of dry burning failure of electric heater

A dry-burn condition occurs when an electric heater is heating with no water in the water tank or with the water level falling below a certain level. This condition is not a set operating state; it is an unexpected system error, a malfunction. A prolonged dry-burn condition can lead to more serious consequences.

Currently, electric heaters on the market are generally equipped with various temperature controllers or thermal protectors. These devices disconnect the circuit and stop heating when the temperature at a test point reaches a set value. The device also automatically closes when the water temperature at the test point drops below a lower limit. When an electric heater "dry-burns" in a water tank, the high heat generated by the heater is transferred to the water tank connection, repeatedly heating it and damaging the seals (gaskets), insulation, and water tank. Compared to most "fast-heating" electric heaters, a fully cast aluminum heater with a die-cast heating element and sealing surface integrated into one unit experiences a faster and higher temperature rise at the water tank junction during dry-burning, accelerating the aging of the seals and causing greater damage.

When an electric heater is inserted into the water tank, it becomes a storage-type electric water heater. Storage-type electric water heaters, however, have developed a comprehensive production technology management system and implementation standards through long-term use. In addition to an automatic reset thermostat, these storage-type electric water heaters must also be equipped with a non-automatic reset device specifically designed to prevent dry-boil. This non-automatic reset device forcibly disconnects the circuit and terminates heating when the amount of water in the water heater falls below a certain level, thus preventing the serious consequences of dry-boil accidents.