Robertshaw 780-783 Hot Surface Ignition Control Module with 34 Second Prepurge

The Robertshaw 780-783 is a hot surface ignition control module designed for reliable operation in gas-fired heating systems. This module features a 34-second prepurge timer and serves as a direct replacement for Rheem OEM part number 62-22578-01, making it ideal for furnace and heating system repairs and replacements.

Key Features:

• Control voltage: 24 VAC with supply voltage options of 120/24 VAC
• 1.5 amp maximum valve current rating
• 17 to 34 second warm-up time with 34-second prepurge capability
• CSA certified for safety and reliability
• Three ignition attempts before lockout with automatic safety shutoff
• Operates in temperatures from -40°F to 176°F
• Compatible with remote sensor systems

How It Works: When the thermostat calls for heat, the module initiates a prepurge cycle before energizing the ignitor. After the warm-up period, the gas valve opens to supply gas to the main burner. The ignitor then turns off and the sensor monitors flame presence. As long as flame is detected, the system continues to operate. If ignition fails after three attempts, the module provides complete lockout and gas shutoff for safety.

This genuine OEM Robertshaw ignition module reduces inventory requirements and provides easy installation with complete instructions. Cross-references include model number HS780-34PL-308A.