Replace The Electronic Control Board; Replace The User Interface - Friedrich Wallmaster WCT08A10A Service Manual

Replace the Electronic Control Board

ELECTRIC SHOCK HAZARD
Turn off electric power before service or
installation. Extreme care must be used, if it
becomes necessary to work on equipment with
power applied.
Failure to do so could result in serious injury or
death.
User Interface
3 ea Control
panel screws
2 ea User
Interface screws
(Electronic Control Board and User Interface Replacement)

Replace the User Interface

1.Unplug the Unit
2.Remove the Front Cover. Refer to Routine Maintenace, Figure 401.
3. Slide the unit out approximately 3 inches from the sleeve.
4. Using a sharp knife, cut slits in the Chassis gasket seal where the control board panel will be opened to avoid
damaging the gasket.
5. Remove two (2) screws from the top, and one (1) from the front of the control board panel and open panel.
6. Remove two (2) mounting screws securing UI and disconnect ribbon cable.
7. Inspect ribbon cable for obvious signs of damage.
8. If ribbon cable is damaged, or damage is suspected, disconnect cable from User Interface and Control Board.
9. Paying careful attention to the ribbon cable routing, remove the old cable and replace with a new ribbon cable.
10. Connect ribbon cable to the power board and user interface as required.
11. Install new UI using the 2-screws.
12.Install the 3 Control Panel Screws.
13. Plug in the unit and verify control operation. Refer to Operation Section.
60
COMPONENT TESTING
WARNING
Figure 712
1. Unplug the unit
2. Remove the Front Cover. Refer to Routine
Maintenance, Figure 401.
3. Slide the unit out approximately 3 inches
from the sleeve.
4. Using a sharp knife, cut slits in the Chassis
gasket seal where the control board panel will
be opened to avoid damaging the gasket.
5. Remove two (2) screws from the top, and one
(1) from the front of the control board panel and
open panel.
5. Remove the four(4) circuit Board pins using
needle nose pliers or other suitable tool.
6. Swap wires one for one from old control
board to new control board. If swapping
Control Panel
wires one for one is not possible, identify and
tag wires. Refer to the wiring diagrams as
4 ea
Circuit required.
Board
7. Install the control board using four(4) new
Pins
circuit board pins.
8. Reinstall the control board panel, with three
(3) screws reinstall the screw in the electronic
Circuit
holder, and secure wiring as required.
Board
9. Install the Front Cover (refer to Routine
Maintenance, Figure 401)
10. Plug in the unit and test the unit for proper
operation. Refer to operation section.