Heater bundle is the mechanism that has direct contact with the heated medium. The lifetime will definitely depend on maintaining element heat transfer efficiency, quality of the medium, and cleaning of heating element periodically. While for heater control panel, it depends on the quality of the selected components such as thyristor/Silicon -Controlled Rectifier (SCR), trip unit/device and earth leakage relay. The lesser the quality of the component, the higher risk of failure.

(i.e. Purity of medium, more carbon, faster, and more scaling build up on the heating elements). The more scale build-up, the more load needs to heat as the efficiency in heat transfer drop.