77 PB
COMPONENT TESTING
Replace the Electronic Control Board - Wallmaster
WARNING
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.
1. Unplug the unit
2. Remove the Front Cover. Refer to Routine Maintenance,
Figure 403.
3. Slide the unit out approximately 3 inches from the sleeve.
Refer to gure 506 for chassis removal.
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.
Figure 720
6. Swap wires one for one from old control board to new
control board. If swapping wires one for one is not possible,
identify and tag wires. Refer to the wiring diagrams as
required.
7. Install the control board using four(4) new circuit board
pins. Remove User Interface to gain access to the pins. Refer
to Figure 720
8. Reinstall the control board panel, with three (3) screws
reinstall the screw in the electronic holder, and secure wiring
as required.
9. Install the Front Cover (refer to Routine Maintenance).
10. Plug in the unit and test the unit for proper operation.
Refer to operation section.
Figure 721
User Interface
3 ea Control
panel screws
2 ea User
Interface screws
Control Panel
4 ea
Circuit
Board
Pins
Circuit
Board
To Next Page
Loading...
Need help?
General
