This is a clear sign the unit needs immediate replacement

you ensure correct coil resistance and contact alignment

Whether you are performing a seasonal tune-up or troubleshooting a burner lockout

This is a Normally Open (NO) switch

the SPDT blower relay configuration is specifically designed to switch between two circuits

Robertshaw 1751-721 Wiring Harness This is a clear signThe Robertshaw 1751 721 Ignitor Sensor Wiring Harness is a critical field service component engineered for flame rectification systems in residential and commercial heating applications. This 48 inch 2 wire ignition harness provides the necessary link between the ignitor sensor assembly and the ignition control module, ensuring high integrity signal transmission for consistent flame sensing. Designed for high heat environments, the 1751 721 harness