Honeywell SV9501M8129 1/2"x1/2" NPT Intermittent Hot Surface Pilot Igniter. The SmartValve System Controls provide easy field replacement of a wide range of SV9500, SV9501, SV9502 and SV9602 SmartValve System models. Gas appliance manufacturers use these models in many types of gas fired heating appliances including central furnaces, residential boilers, rooftop furnaces, commercial cooking appliances, and unit heaters. These controls provide intermittent pilot gas ignition sequencing, pilot flame sensing, and both pilot and main gas control functions in a single control. They are directly compatible with the Q3450 or Q3480 intermittent Pilot burners used with the original controls on the appliance.