Electric storage heater

An electric storage heater uses one or more containers 7 for a phase change heat storage medium which changes its state at a relatively low temperature, say less than 70 DEG C. Air drawn in towards the lower end of the heater 5 emerges from the upper end 6 after having passed over the surface of the containers containing the phase change material. The relatively low temperature of operation permits the output flow to be controlled by a damper (not shown) which provides a variable restriction to the outlet 6. <IMAGE>