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Furnace Control Kit, HSI Integrated, Universal, Two Stage, Variable Speed ECM Circulator, 120 Vac


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Manufacturer Part No:
Newark Part No.:
Technical Datasheet:
21V51U-843   Datasheet
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Product Information

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Ignition Ctrl Mod, Wiring Harness, Universal Ignitor Kit, Installation Instructions & OEM Cross-Ref


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Technical Docs (2)

Product Overview

The 21V51U-843 from White Rodgers is a universal two-stage HSI integrated variable-speed (ECM) circulator furnace control kit. 21V51U-843 simplifies stocking, installation and ensures peak system performance. Easy-Install Kit includes everything user need for quick and accurate replacement. The kit has 50V51-843 two-stage automatic gas interrupted ignition control employing a microprocessor to continually monitor, analyse 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.
  • Input voltage of 24VAC, 60Hz (class II transformer required)
  • 120VAC ignitor, two-speed inducer, humidifier, electronic air cleaner o/p
  • Nominal input current at 24VAC at 595mA + MV
  • Gas valve relays of 1.5A at 24VAC, 60Hz, inducer relays of 2.2 FLA to 3.5 LRA at 120VAC, 60Hz
  • Humidifier load of 1A max at 120VAC, electronic air cleaner load of 1A max at 120VAC, 60Hz
  • Ignitor relay at 4A max at 132VAC, 60Hz
  • Operating temperature range from -40°F to 175°F (-40°C to 80°C)
  • Dimension is 5.25" W x 8" H x 1.25" D
  • Fuse protection is 3A, furnace status LED, CFM LED
  • Natural, manufactured, mixed, liquefied petroleum and LP gas air mixtures are approved gases for use


Automation & Process Control


50V51-843 ignition control module, Wiring harnesses for amana/goodman, 21D64-2 HotRod™ universal ignitor kit, Installation instructions, OEM cross-reference.

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