Honeywell pipe plug 45900402-041U F55 45900402-041U

This boiler pipe fitting, model 45900402-041U F55, is a threaded plug with an M11x1 metric fine thread. It is made of gas and temperature-resistant metal. It is used to seal unused outlets on Honeywell VR4601 series gas valves and is also compatible with Honeywell heating boilers, burners, gas systems, and industrial and domestic gas equipment. The plug provides a hermetic seal to prevent gas leaks from unused ports.

When selecting a replacement plug of this class, match the thread size and pitch (M11x1) to the port. Confirm whether the port is parallel (ISO 228/1) or taper (ISO 7/1), as sealing methods differ: parallel threads use a sealing washer or O-ring, taper threads use PTFE tape or thread compound. The plug material must be compatible with the medium and pressure; for gas trains, brass or steel plugs are common. During installation, avoid overtightening, which can deform the thread or crack the housing. Check the plug for burrs and the seal condition before reuse.