White-Rodgers WR 21V51U-843 HSI FRNC CTRL

The 50V51-843 is a two stage automatic gas interrupted ignition control employing a microprocessor to continually monitor, analyze, and control the proper operation of the gas burner and inducer. the 50V51-843 provides signals for proper operation of a variable fan speed circulator blower signals interpreted during continual surveillance of the two stage thermostat and flame sensing element initiate automatic ignition of the burner, sensing of the flame, and system shutoff during normal operation. the control incorporates system fault analysis for quick gas flow shutoff coupled with automatic ignition retry upon sensing a fault correction.

21D64-2 Silicon Nitride Igniter Upgrade Kit

• 16-pin variable speed circulator output for ECM
• Dipswitch selectable for OEM applications two-speed inducer output, two stage gas valve output
• Pushbutton fault history retrieval
• Furnace status LED - tri-color (green, red and amber)
• Heat fan off delay (dipswitch selectable), fan on delay for cooling
• -40 to 175 deg F
• 2-stage gas valve output
• 3 A fuse protection
• Pressure switch inputs and monitoring
• Flash microprocessor with non-volatile memory
• Flame current measurement points
• 1.5 A valve relay
• 2.2 FLA to 3.5 LRA inducer relay
• 14.5 FLA to 25 LRA circulator relay
• 1 a max at 120 VAC humidity
• 1 a max at 120 VAC electronic air cleaning
• 4 a max at 132 VAC ignitor relay
• 0.3 uA DC max current for flame detection
• 0.1 uA DC min current for flame detection
• 100 M ohm leakage resistance, 3 speed PSC blower motor systems

CSA Certified