Lennox 79L57 Orifice 320788-702 preventing the common "squirrel cage"

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

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

To ensure proper drainage and operation of the lift lever

you know that field-converted or "universal" valves often lead to hunting issues or improper evaporator loading

Lennox 79L57 Orifice 320788-702 preventing the common "squirrel cage"The 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