ELECTRONIC CONTROL BOARD (PWA) REPLACEMENT
7309374 (Rev. C 7/17/19)
9. With the correct model code displayed, press the SELECT button.
The electronic controller will restart, briefly displaying the nodel
code you set.
10. Press the UP (È) or DOWN (–) buttons to set the present time.
Up moves the display ahead; down sets the time back. Be sure
AM or PM is correct.
NOTE: Press buttons and quickly release to slowly advance the
display. Hold the buttons down for fast advance.
11. Press the SELECT button a few times, until the time appears on
the display, but is not flashing.
12. For information about programming additional features of the
softener, consult your owner’s manual.
13. If the valve is not in Service position, press the RECHARGE button
and hold for 3 seconds to start a recharge cycle. The display will
flash “RECHARGE NOW.” In about 2 hours the recharge cycle will
be complete and the valve and electronic control board will be
properly oriented together.
NOTE: To save time, use the manual advance procedures to properly
time and check operation. See service information in the
manual.
Model Number
Model Code
to select
NSC15ED Sr14
NSC25ED or NST25ED Sr20
NST30ED SR30
NST45ED1 SR45
NST70ED1 SR70
EP15 EP15
Figure 3
RECHARGE
button
SELECT
button
Display
DOWN
button
UP button
6. Reconnect the wiring to the new board (See Figure 2).
7. Plug the power supply into the electrical outlet. A number shows in
the display for a few seconds, followed by a flashing “- - - - -”.
NOTE: If “- - - - -” is not flashing in the display, press and hold the
SELECT button until a model code appears.
8. Use the UP (È) or DOWN (–) buttons to set the correct model code
for your softener (see table below).
Figure 1
IMPORTANT: BE SURE THE VALVE CAM INDI-
CATES “SERVICE” POSITION (See Figure 1)
WHEN REPLACING THE ELECTRONIC
CONTROL BOARD (PWA), TO ASSURE BOTH
VALVE AND PWA ARE ORIENTED, OR TIMED,
TO THE SAME CYCLE. If the valve is not in
Service position, see step 13 below.
NOTE: When installing the electronic control
b
oard (PWA) on the faceplate, use care not to
twist the circuit board, or force it onto the
mounting pegs. Twisting could damage the printed
circuits, or break the display glass.
1. Unplug the system’s power supply.
2. Remove the faceplate cover to expose the valve.
3. Unplug the wiring connections from the back of
the old Electronic Control Board (See Figure 2).
4. Carefully remove the old board by unsnapping it
from its retainer tabs.
5. Carefully snap the new Electronic Control Board
into the retainer tabs.
1” Valve
MOTOR
CAM
Position markers
(valve in service)
Position markers
(
valve in service)
CAM
MOTOR
3/4” Valve
Figure 2
Power
Supply
Back of Electronic
Control Board
Valve
Motor
Turbine
Sensor
Valve Position
Switch
