Lennox 79L57 Orifice 320788-702 this unit is versatile and

this unit is versatile and supports conventional 1H/1C systems as well as heat pump applications by configuring the system switches during installation

It is purpose-built to maintain the atmospheric pressure reference required for proper diaphragm operation while shielding the vent orifice from blockage caused by freezing rain

preventing the common "squirrel cage" scraping noises and vibration-induced wear that often plague aftermarket alternatives

Built with a brass body and reinforced diaphragms

Lennox 79L57 Orifice 320788-702 this unit is versatile andThe Lennox 79L57 is a critical Natural Gas Burner Orifice engineered specifically for high efficiency Lennox gas furnaces and heating units. This genuine OEM replacement part is precision machined to deliver an exact BTU output by regulating the volumetric flow of natural gas to the burner assembly. Using a Lennox 79L57 Orifice ensures your manifold pressure aligns with factory specifications, preventing issues like incomplete combustion, soot