Important OEM Replacement Instructions

INSTALLER MUST READ FOR PROPER

INSTALLATION

•Wiring harnesses and a Universal 21D64-2 ignitor are included in this package. Refer to the enclosed “Cross

Reference and Harness Application Chart” (Part Number

37-7077) for harness selection and ignitor application information. Ignitor installation instructions are in the

UNIVERSAL 21D64-2 Ignitor package included with this kit.

•IMPORTANT: For continuous fan speed operation, one of the unused parked motor taps must be connected to the low heat speed terminal. Failure to do this will result in the blower not energizing in the constant fan mode operation.

Refer to figure 1.

•Installer must read Page (6) “Operation” and follow option switch setting for proper control operation.

•In certain applications it may be necessary to remove the control board from the cover to be mounted in the space allowed. Standoffs supplied in the package must be installed before the control board can be mounted.

•4 Blower lead extensions are included in the kit if extra length is needed to complete installation.

•TRANE and AMERICAN STANDARD

For all TRANE and AMERICAN STANDARD furnaces only: Install jumper 0151 290600 (included in this package) into the back of the furnace 12 pin connector harness from pin 5 to pin 11 as shown in Figure 2.

Make sure jumper snaps into the connector securely.

•RHEEM / RUUD (1994 and earlier models)

If the furnace control being replaced has 2 green lights and NO amber light (furnace date code 3294 or earlier) a Flame Sensor Kit, RHEEM Part Number 62-24044-71

(not available from White-Rodgers) is required. Install the flame sensor and plug the flame sensor lead into pin 7 of the connector on the furnace as detailed in the Rheem Flame Sensor Kit instructions. Plug the furnace connector into harness “B” (included in this package). Plug the other end of harness “B” into the new module. Attach the orange wire from harness “B” (3/16” female spade terminal) to FS on the new module to complete the flame sense circuit.

•BRYANT / CARRIER / DAY & NIGHT / PAYNE

This kit will not replace BRYANT / CARRIER / DAY & NIGHT / PAYNE HK42FZ013 modules or CARRIER / BDP modules using an 11 pin (straight) connector.

Refer to the enclosed “Cross Reference and Harness

Application Chart” (Instruction sheet Part Number 37-

7077) included with this kit for the list of modules it replaces.

INSTALLATION

Figure 1	For continuous fan speed
	For continuous fan speed
	connect one of the unused
	parked terminals here

Pin 11 (RO In)

Jumper 0151-290600 (for Trane and American Standard applications only)

290600 J

Pin 5 (RO Out)

Figure 2. 12 Pin Connector (back view) on existing Wire Harness in Furnace

50M56U-843 specifications

The White Rodgers 50M56U-843 is a versatile and reliable universal thermostat known for its innovative features and user-friendly design. This device is particularly popular among homeowners looking to optimize their HVAC systems for improved comfort and energy efficiency.

One of the standout features of the 50M56U-843 is its compatibility with a wide range of heating and cooling systems. This includes conventional and heat pump systems, making it an excellent choice for various types of home environments. The thermostat supports both single-stage and multi-stage systems, allowing for comprehensive climate control tailored to specific needs.

The 50M56U-843 boasts an easy-to-read backlit display that provides clear visibility in low-light conditions. This user-friendly interface makes programming and setting adjustments straightforward, ensuring that users can quickly and easily modify settings for maximum comfort. The thermostat's simple navigation menu allows users to adjust temperatures, set schedules, and switch between heating and cooling modes with ease.

Efficiency is a key focus for the White Rodgers 50M56U-843, as it offers advanced energy-saving features. Users can take advantage of programmable settings that allow the thermostat to adjust temperatures based on daily routines, thus reducing energy consumption during times when the home is unoccupied. This feature not only saves on utility bills but also promotes environmentally friendly practices.

In terms of technological advancements, the 50M56U-843 incorporates features such as auto changeover, which allows the thermostat to automatically switch between heating and cooling modes as needed. This ensures optimal comfort without the need for constant manual adjustments. The unit also supports a wide temperature range, accommodating various climate conditions.

Another notable characteristic is its easy installation process. The 50M56U-843 is designed with user-friendliness in mind, providing clear instructions for mounting and wiring. This makes it feasible for homeowners to install the thermostat themselves without requiring professional assistance.

In summary, the White Rodgers 50M56U-843 is a dependable and efficient thermostat that combines functionality with user convenience. Its versatility, energy-saving features, and easy installation make it an ideal choice for those looking to enhance their home’s heating and cooling efficiency, while ensuring a comfortable living environment year-round.