Lennox 50M18 Ring, Cap, & Plug While the UV bulb is

While the UV bulb is replaced annually

making it a staple for technicians maintaining boilers

it provides the exact resistance values and switching points required by the control board to prevent short-cycling and unnecessary auxiliary heat engagement

provided the internal bore matches the capillary diameter

Key Benefits OEM Compatibility: Specifically engineered to fit Carrier

Lennox 50M18 Ring, Cap, & Plug While the UV bulb isThe Lennox 50M18 Ring, Cap, & Plug is a factory direct OEM replacement kit (LB 101508A) critical for maintaining the pressure integrity of Lennox gas furnaces and air handlers. As an essential HVAC repair part, this kit includes a high grade rubber ring, protective cap, and sealing plug designed to secure line openings and block unused ports within the ducting or piping assembly. Field technicians frequently utilize the Lennox 50M18 to prevent air