Johnson & Starley Pilot Burner Assembly Non ASD SIT BOS02397/1

The BOS02397/1 is a pilot burner assembly supplied by Johnson & Starley for its warm air units and water heaters. It is the non-ASD SIT type, meaning it uses a SIT pilot arrangement without the automatic shut-off device variant, and it provides the standing flame that lights the main burner and proves ignition at the flame sensing point.

This assembly is used across a broad spread of Johnson & Starley appliances, from the Economaire warm air range through to the Eljan water heater and the Hi-Spec M31. It is a gas-carrying component, so replacement is a job for a Gas Safe registered engineer.

• The pilot will not light at all, or lights only intermittently when the ignition sequence is run.
• The pilot flame lights but will not hold once the control knob is released.
• The pilot flame is weak, lazy or noticeably yellow rather than a steady blue.
• Sooting, blackening or carbon deposits around the pilot head or injector area.
• Repeated lockouts or ignition faults traced to the pilot not proving to the flame sensing circuit.

• Check the GC number and model on the appliance data plate against the compatibility list to confirm the correct pilot assembly.
• Confirm the existing pilot is the non ASD SIT type before ordering, as the assembly is variant-specific.
• Check whether a gasket or seal is required when refitting the pilot assembly to the burner.
• This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.