White Rodgers 50M56U-843 User Manual
Installation instructions, Description, Precautions

www.white-rodgers.com
50M56U-843
Universal Single Stage
HSI Integrated Furnace Control Kit
INSTALLATION INSTRUCTIONS
FAILURE TO READ AND FOLLOW ALL INSTRUCTIONS
CAREFULLY BEFORE INSTALLING OR OPERATING
THIS CONTROL COULD CAUSE PERSONAL INJURY
AND/OR PROPERTY DAMAGE.
DESCRIPTION
The 50M56U-843 kit is a Universal Single Stage HSI Integrated
Furnace Control that employs a microprocessor to continually
monitor, analyze, and control the proper operation of the gas
burner, inducer, and fan.
The kit contains:
• 50M56-843 Ignition Control Module
• 21D64-2 Ignitor Kit
• Set of Interconnect Harnesses
Installation should be done by a qualified heating and air
conditioning contractor or licensed electrician.
If in doubt about whether your wiring is millivolt, line, or low
voltage, have it inspected by a qualified heating and air
conditioning contractor or licensed electrician.
Do not exceed the specification ratings.
All wiring must conform to local and national electrical codes
and ordinances.
This control is a precision instrument, and should be handled
carefully. Rough handling or distorting components could
cause the control to malfunction.
Following installation or replacement, follow manufacturer’s
recommended installation/service instructions to ensure
proper operation.
PRECAUTIONS
PART NO. 37-7042B
Replaces 37-7042A
0937
Do not short out terminals on gas valve or primary
control. Short or incorrect wiring may damage the
thermostat.
CAUTION
!
Failure to comply with the following warnings could result
in personal injury or property damage.
FIRE HAZARD
• Do not exceed the specified voltage.
• Replace existing control with exact model and
dash number.
• Protect the control from direct contact with water
(dripping, spraying, rain, etc.).
• If the control has been in direct contact with
water, replace the control.
• Label all wires before disconnection when serv-
icing controls. Wiring errors can cause improper
and dangerous operation.
• Route and secure wiring away from flame.
SHOCK HAZARD
• Disconnect electric power before servicing.
• Ensure proper earth grounding of appliance.
• Ensure proper connection of line neutral and line
hot wires.
EXPLOSION HAZARD
• Shut off main gas to appliance until installation
is complete.
WARNING
!
THE SUPPLIED WIRING HARNESSES ALLOW
THE “UNIVERSAL 50M56U-843” TO BE USED
IN NUMEROUS APPLICATIONS. FOR PROPER
INSTALLATION THE INSTALLER MUST READ
“PAGE 2 AND 3” MOUNTING AND WIRING.
INSTALLER MUST READ
CONTENTS
Description ................................................................... 1
Precautions .................................................................. 1
Specifications .............................................................. 2
Installation ................................................................... 2
Mounting & Wiring
Operation ..................................................................... 7
50M56-843
21D64-2