Gas fired water heater flame sensor - has expansion bulb with capillary operating diaphragm sealed gas flap actuator

摘要

The safety and control system for fuel gas fired water heater has long life flame sensor. The latter is a small air filled fessel connected by capillary tube to a membrane chamber for actuating gas supply valve. The diaphragm (9) is not in direct contact with the fuel gas. Movements of this diaphragm are transmitted to gas flow regulating flap (7) by a push rod (16) which acts on another sealed diaphragm (17). The latter carries plunger which is in direct contact with the flap. The sealed mechanism ensures long life of the components.