Robertshaw 780-787 Ignition Module

The Robertshaw 780-787 Ignition Module is a professional-grade Hot Surface Ignition (HSI) Control engineered for high-reliability performance in gas-fired heating systems. This specific unit is a direct replacement for the HS780-34NR-306A, maintaining exact electrical and mechanical specifications for seamless field installation. Operating on a 120V AC supply voltage with a 24V AC control input, this module features a 34-second ignitor warm-up period and a 6-second valve trial for ignition. Designed for versatility, it supports both local and remote flame sensing configurations and includes three ignition attempts before initiating a safety lockout. The compact housing, equipped with molded-in terminal barriers and a dedicated mounting ground screw, ensures a secure and efficient footprint within the furnace cabinet or appliance control area, making it a standard choice for technicians servicing residential and commercial 24VAC gas valve applications.

Key Benefits

• Direct Cross-Reference: Serves as an identical replacement for HS780-34NR-306A, ensuring zero-modification compatibility.
• Flexible Flame Sensing: Compatible with remote flame sense and local sense setups to accommodate various burner configurations.
• Safety Logic: Integrated 3-trial lockout protection prevents hazardous gas accumulation during ignition failure.
• Thermal Range: Rated for ambient temperatures between -40°F and 176°F, providing stability in unconditioned spaces.
• Simplified Wiring: Molded-in barriers between 1/4-inch terminals reduce the risk of short-circuiting during high-voltage terminations.

Common Questions

Does this module replace the HS780-34NR-306A version?
Yes, the 780-787 is the direct technical equivalent to the HS780-34NR-306A ignition control, matching its timing and electrical ratings perfectly.

What is the reset procedure after a safety lockout?
To reset the module following a lockout, the thermostat or system switch must be opened for a minimum of 10 seconds to cycle the internal logic.

Can this be used with a 24V hot surface igniter?
No, this module is specifically configured for 120V AC HSI igniters. Using it with a 24V igniter will result in immediate component failure.

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.