White-Rodgers Control,Hot Surface Ignition,2 Retries 21M51U-843

• Includes Trane Ignitor Mounting Bracket
• Standards CSA Certified
• For use with Residential, Commercial Heating Equipment

Features:

• 120 VAC Igniter Output
• 120 VAC Two-Speed Inducer Output
• 120 VAC Humidifier Output
• 120 VAC Electronic Air Cleaner Output
• 120 VAC 3-Speed PSC Circulator Output
• 2-Stage Gas Valve Output
• Fuse Protection – 3 Amp
• Furnace Status LED – Tri-Color (Green, Red and Amber)
• Heat Fan OFF Delay (Dipswitch Selectable)
• Fan ON Delay for Cooling
• Auto Second Stage Delay (Dipswitch Selectable Mode)
• Historical fault retrieval by pushbutton
• YLO, Y, W1, W2, R, G, C, TWIN terminals
• Pressure switch inputs and monitoring
• Flash microprocessor with non-volatile memory
• Flame current measurement points

Replaces: 

• White-Rodgers 50M51-242 and all 50M61-xxx’s Two-Stage HSI systems with 80V or 120V Igniter
• Easy Install Kit includes everything you need for quick and accurate replacement
• Ignition Control Module
• Universal 120V Nitride Igniter Kit – 21D64-2
• Installation Instructions and OEM Cross-Reference