Lennox 78L42 Gas Valve

The Lennox 78L42 is a high-performance 24V 2-stage gas valve engineered for precision fuel regulation in residential and light commercial forced-air systems. This genuine OEM Lennox replacement part, often cross-referenced as 78L4201, is manufactured by Honeywell (Model VR8205Q2662) to ensure seamless integration with Lennox G32 and GHR32 series furnaces. Featuring a 1/2" NPT inlet and outlet, this natural gas valve supports dual-stage heating, allowing for a low-fire manifold pressure of approximately 1.7" W.C. and a high-fire setting of 3.5" W.C. This functionality is critical for maintaining thermal equilibrium and improving system efficiency during varying load demands. Designed for direct spark ignition (DSI) and hot surface ignition (HSI) systems, the 78L42 furnace gas valve replaces legacy components including 61L11 and 61L1101. As a 24 volt HVAC gas control, it utilizes standard 1/4" male quick-connect terminals for a secure electrical interface, ensuring reliable communication with the furnace primary ignition control.

• Precise 2-Stage Control: Enables variable heating output, reducing cycling and improving overall furnace performance.
• Universal Compatibility: Serves as a direct 78L4201 replacement for Lennox, Armstrong, and Ducane heating units.
• Optimized Flow Rate: Engineered with a 1/2 inch NPT connection to maintain consistent pressure for natural gas applications.
• Dual Stage Efficiency: Supports lower firing rates for mild weather, maximizing energy conservation without sacrificing comfort.

Is the Lennox 78L42 compatible with LP (Propane)?
This valve is factory-configured for natural gas. While the VR8205 series can typically be converted, a specific LP conversion kit must be sourced and installed by a licensed technician.

Does this valve replace the 78L4201 model?
Yes, the Lennox 78L42 and 78L4201 are functionally identical parts and can be used interchangeably in all specified Lennox furnace models.

What are the electrical requirements for installation?
The valve operates on a 24VAC circuit at 60Hz with a typical current draw of 0.70 Amps, connecting via standard 1/4" quick-connect terminals.

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.