FLAME FAILURE DEVICE

摘要

A flame failure device for a gas-fired appliance has a heat sensitive device (24') in the form of fine bore tube (25). The tube is connected to one chamber (10) of a pressure sensitive gas flow control valve assembly. The chamber is pressurized and the rate of flow from the chamber is controlled by flow through the fine bore tube (25) the application of heat to which reduces the rate of flow through the fine bore tube (25) while the withdrawal of heat restores the rate of flow. Heat is provided by a gas burner of the appliance. The fine bore tube may have a non-circular cross-section and be formed by deforming part at least of a length of tubing (FIGS. 4A and 5B).