Hercules Product Info
Hercules Product Id 21M51U-843
Product Description UNIVERSAL 2 STAGE CONT BOARD
Unit of Measure EA
Manufacturer Info
Manufacturer Name Copeland
Brand Name White-Rodgers
Part Number 21M51U-843
Product UPC 786710540707
Product Description White-Rodgers 21M51U-843 Universal Hot Surface Ignition Control, 25 VAC, 530 mA
Product Features
Includes: 21D64-2 Silicon Nitride Igniter Upgrade Kit
120 VAC 3 speed PSC circulator output, 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
Auto second stage delay (dipswitch selectable)
-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
Product Documents
Document Type Download Link
Catalog 21M51U-843_Catalog (pdf)
Specification Sheet 21M51U-843_Specification Sheet (pdf)
Product Specifications
Accessory Type Hot Surface Ignition Control
Amperage Rating 530 mA
Depth 1-1/4 mA
Domestic/Import Import
Electrical Connections 1/4 in Spade Terminal and Molex Plug
Gas Type Liquid Propane/Natural Gas
Height 8 in
Igniter Warm-Up Time 17 s
Lead Length 15-1/2 in
Probe Length 15-1/2 in
Type Universal
Voltage Rating 25 VAC
Width 5-1/4 in
Certifications CSA Certified
Country of Origin MX