GB1437698A - Control apparatus for burners - Google Patents

Abstract

1437698 Controlling burners SIOUX STEAM CLEANER CORP 20 March 1974 [29 May 1973] 12339/74 Heading F4T and F4F A burner apparatus 10, Fig. 2, for heating water is turned on in stages comprising establishing a spark at igniter 14 if a plurality of operating conditions are within predetermined ranges, allowing fuel flow to jet 16 to form a low flame when a sensor 40 detects a spark, and allowing fuel flow to jet 18 to form a higher flame when a sensor 42 detects a flame at jet 16. The control circuitry, Fig. 1, comprises switches 70, 72, 74 in series with power source 78 and the primary winding of ignition transformer 76 so that the latter can only be energized when the switches provide continuity. This state exists if a sensor 11 detects that the temperature of the water to be heated is less than, e.g. 205‹ F., a sensor 56 detects suitable water flow in pipe 54, and a sensor 60 detects suitable combustion air pressure. Energization of transformer 76 causes sparking at igniter 14. Sensor 40 thus energizes relay 80 causing the latter to move downwardly to supply current through line 141 to valve solenoid 36. Valve 32 therefore opens to supply liquid fuel through line 24 to form a low flame at jet 16. The flame sensor 42 consequently energizes relay 90 to supply current through line 145 to valve solenoid 38, providing switch 92 has been closed by sensor 13 detecting a water temperature below, e.g. 195‹ F. Valve 34 thus opens to supply fuel through line 26 to form a higher flame at jet 18. Indicator circuitry (Fig. 3, not shown) includes relays (100-105) and indicator lights (110-115) to indicate completion of the different turn-on stages or the occurrence of unsuitable operating conditions.