What is the primary cause of clicking but no ignition with this pilot

Is this a balanced port design

F cut-in to prevent component damage due to overheating

featuring a durable diaphragm that resists fatigue over thousands of cycles

Armstrong International D41790 Air Vent 30067439-890 What is the primary causeThe Armstrong International D41790, also identified as the AV 13 brass air vent, is a specialized automatic air vent designed for hydronic heating systems and hot water service. Featuring a dual connection design with 1 2" female NPT and 3 4" male NPT ports, this float actuated valve effectively manages air binding by purging accumulated air during system operation. Constructed from high grade brass, the unit is rated for operating pressures up to 150