If the new unit is smaller

Propane requires a significantly smaller orifice diameter due to its higher energy density

We recommend using this part strictly with the intended Honeywell series to ensure a proper NEMA-rated seal

suitable for standard temperature duct environments

Common causes include a cracked heat exchanger

Lochinvar & A.O. Smith 100233587 Burner Gasket If the new unit isWhen you are performing annual maintenance on a high efficiency Lochinvar Knight or A. O. Smith system, ensuring a gastight seal at the burner assembly is non negotiable. The Lochinvar & A. O. Smith 100233587 Combustion Burner Gasket is the professional grade OEM solution designed to prevent the escape of hazardous combustion byproducts and maintain the precise pressure balance required for condensing boiler efficiency. This specific boiler burner