Installation – White Rodgers 50M56U-843 User Manual
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INSTALLER MUST READ FOR PROPER
INSTALLATION
•
Wiring harnesses are included in this package to complete
the installation of the
“UNIVERSAL 50M56U-843” for the
listed applications. See 37-7077.
•
Refer to Harness Application Charts 37-7077 for proper wire
harness and ignitor selection.
•
Installer must read Page (6) “Operation” and follow switch
setting for proper control operation.
•
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.
•
For replacing the ignitor, a
UNIVERSAL 21D64-2 is included.
For proper installation, refer to the instructions included in
the 21D64-2 kit.
•
FOR ALL TRANE AND AMERICAN STANDARD APPLI-
CATIONS ONLY: Install jumper 0151 290600 (included in
this package) in the furnace 12 pin connector harness, pin 5
and pin 11 positions. Make sure jumper snaps into the con-
nector securely. Refer to figure 2.
•
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.
INSTALLATION
For continuous fan speed
connect one of the unused
parked terminals here
The 50M56U-843 has only one serviceable part–an automotive
type fuse, which protects the low voltage transformer from
damage if the output is short-circuited. If the fuse has opened
up, remove whatever caused the short circuit and replace
the fuse with only a 3 Amp automotive type fuse. If the fuse
does not correct the condition, replace the entire 50M56U-843
control. There are no other user serviceable parts.
Figure 1
290600
J
Pin 11 (R10 In)
Pin 5 (R10 Out)
Jumper 0151-290600
(for Trane and American
Standard Applications only)
Figure 2. 12 Pin Connector (back view)
on existing Wire Harness in Furnace