Nordyne 661018 Orifice

For technicians servicing forced-air systems, the Nordyne 661018 Orifice is a precision-engineered #18 natural gas burner orifice designed for specific BTU outputs in Miller and Intertherm gas furnaces. This OEM Nordyne part ensures accurate gas-to-air mixing ratios, maintaining optimal combustion efficiency and preventing carbon monoxide buildup due to improper flame characteristics. As a #18 drill size orifice, this component is calibrated for natural gas furnace manifold pressure, ensuring a stable and reliable ignition sequence. When performing a furnace burner maintenance or a gas valve replacement, ensuring the correct brass orifice sizing is critical for equipment longevity and safety. This part is a direct replacement for Nordyne 661018, manufactured to strict tolerances to manage high-temperature environments within the burner assembly. Using professional-grade HVAC replacement parts like this orifice guarantees that the system operates within manufacturer specifications, reducing call-backs and optimizing residential heating efficiency.

• OEM Compatibility: Precision-fit for Nordyne, Miller, and Interterm gas furnaces.
• Calibrated Performance: Standard #18 natural gas orifice sizing for consistent BTU delivery.
• Durable Brass Construction: High-quality material resists corrosion and thermal stress in the burner box.
• Optimized Combustion: Ensures clean natural gas flame patterns for peak heater performance.
• Direct Replacement: Simplifies repairs during gas furnace burner manifold servicing.

Is the 661018 orifice compatible with LP conversion?
No, this specific part number is a natural gas burner orifice. For propane applications, a dedicated LP conversion kit with a different drill size must be used to match the higher energy density of liquid propane.

What are the symptoms of a clogged or incorrectly sized orifice?
An incorrect orifice drill size can lead to delayed ignition, sooting, or insufficient heat output. If the burner orifice is obstructed by debris, you will typically see localized yellow tipping or a weak flame signal.

How do I ensure the manifold pressure is correct for this orifice?
Always use a digital manometer to verify that the natural gas manifold pressure aligns with the rating plate of the furnace, typically 3.5" W.C. for standard Nordyne heating units.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.