While it fits standard 1/8" OD tubing

As an automatic reset limit control

this L175-40F manual reset control is engineered to interrupt the burner circuit if heat exchanger temperatures exceed the 175°F safety threshold

updated version of the 312800

this 170-degree limit switch is a direct drop-in replacement that maintains original equipment specifications

Fenwal 05-129927-224 Wiring Harness While it fits standard 1/8"The Fenwal 05 129927 224 Wiring Harness is a 24 inch, 6 wire edge connector assembly engineered for precision signal transmission in commercial HVAC ignition systems. Designed specifically for compatibility with Fenwal ignition control modules, this harness ensures a secure, low resistance electrical interface critical for maintaining reliable flame sensing and spark ignition sequences. The 6 pin edge configuration facilitates a seamless "plug and