WIRING
Most furnaces are serviced by simply connecting the OEM wiring
directly to the new 50M56U-751 control.
Exceptions to this rule are
covered below:
NOTE:
Furnaces previously serviced with Carrier 325878-751, ICM 282A, or White-Rodgers 50M56U-751 kits
may have an adapter harness already installed between the factory wiring and the control being replaced. If found,
remove the old adapter harness and replace it with the new one provided in the kit.
NOTE:
Using the “Flip” harness when replacing controls other than HK42FZ018 or failure to use the “Flip” harness
when replacing HK42FZ018 will result in a miswiring that will cause a Limit / Rollout Switch Open Error
(Code 33)
and eventually a Limit / Rollout Switch Lockout
(Code 13)
.
The 11-pin inline connections for these applications are reversed or “flipped” 1 for 1 from the standard pinout. To
allow for this, the “Flip” harness connects pin 1 on the control to pin 11 in the furnace, Pin 2 on control to Pin 10 in
the furnace, etc.
9-Pin Adapter Harness
Used when replacing the following OEM controls:
HK42FZ004, HK42FZ007, HK42FZ008, HK42FZ009, HK42FZ011, HK42FZ016
11-Pin “Flip” Adapter Harness
Used when replacing the following OEM control:
HK42FZ018
Furnace 2-Pin
Furnace 11-Pin
Control Board
Neutrals
Control Board
11-Pin
Control Board
2-Pin
Control Board
11-Pin
Furnace 3-Pin
Furnace 9-Pin
11
10
9
8
7
6
5
4
3
2
1
1
2
3
4
5
6
7
8
9
10
11
2
