31
FIGURE 20.
The ignition control continuously performs various diagnostic
tests to verify proper appliance and control operation. Should an
unsafe condition occur, the control will shut down the burner and
illuminate the appropriate diagnostic indicators on the Display
Board, figure 20, indicating a need for service. All operating
programs are stored in permanent memory on the ignition control
and a second programmable memory is used for retaining user
specific operating parameters in the event main power is ever
interrupted. If a failure lock-out occurs, the board must be reset
by depressing the enter/reset button on the display board,
indicating a need for service.
FIGURE 21. DIA-SCAN II CONTROL AND DISPLAY BOARD
NOTE: PC board jumpers are used on the WHC 1502 (see
figure 21) to control the mode of temperature regulation (tank
probe or 24 V control) and number of ignitions trials (Standard
VS. CSD-1 Models). The jumper is a small rectangular plastic
piece which fits over two control board leads (see figure 22). It
is used on LW models to allow for the use of the tank probe
provided with the unit. If the installer wishes to use an alternate
24-Volt method of temperature control, the J33 jumper must
be removed and the red/green wires in the junction box at the
rear of the unit must be used. (see figure 21 and 22). Standard
LB models will not have a jumper across the J33 board leads.
Wires are provided in the junction box for a 24-Volt method of
temperature control.
LINE POLARITY INDICATOR
A green LED is mounted on the ignition control board to indicate
line voltage polarity is properly connected. When 120 VAC input
power is properly connected to the ignition Control Board, the
green LED will illuminate. If an error is made when connecting
120 VAC input power, this LED will not light. Improperly connecting
the input power may result in a false flame sensor failure.
FUSE PROTECTION
The 24 VAC circuitry is protected with a 3 amp auto fuse. If the
fuse opens, a red LED located near the fuse will light. If the red
LED is illuminated, replace the fuse.
Repeated failure of the
fuse is an indication of possible damage to the ignition control.
Note: An extra fuse and 1 jumper are supplied with the boiler.
FIGURE 22.
DIA-SCAN II DISPLAY BOARD
OPERATING PROCEDURES
The Display Board, figure 20, provides a user friendly interface to
the WHC1502 Ignition Control Board. With the Display Board,
the user can control appliance functions and view the overall
operating status of the appliance. If an error condition occurs,
the Display Board will scroll a diagnostic message across the
LED display. Under normal operating conditions, the four digit
LED display on the Display Board will continuously illustrate the
water temperature sensed at the outlet temperature probe. The
push buttons on the Display Board are connected to the Ignition
Control Board through a 6 conductor cable assembly with modular
plug terminations. In addition, an 8 conductor modular jack on
the Display Board allows for connecting a remote display board.
When power is applied to the WHC1502 System, the Display
Board will initially run through a self-diagnostic test, and then
display the Outlet temperature. If the Tank Probe is connected to
the board the tank temperature will be displayed. To display a
specific setting or temperature, press the SELECT push-button
until the appropriate LED is illuminated (see figure 20). After 5
seconds, the Display Board will automatically revert to display
the Outlet temperature. Pressing the ENTER/RESET push-button
will hold the display in the indicated mode until the SELECT push-
button is pressed.
With the display board, the user can make adjustments to many
of the appliance’s control features. This includes the following:
Содержание LB 1000
Страница 22: ...22 FIGURE 16 CONNECTION DIAGRAM ...
Страница 23: ...23 FIGURE 17 SCHEMATIC DIAGRAM ...
