ELECTRONIC CONTROL BOARD (PWA) REPLACEMENT
7351452 (Rev. A 8/3/15)
9. With
the correct model code displayed, press the SET button
several times, until a flashing “12:00 PM” and “PRESENT TIME”
show in the display.
10. Press the UP (
) 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 SET 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.
Figure 2
Power
Supply
Back
of Electronic
Control Board
Valve
Motor
Turbine
Sensor
Valve Position
Switch
Model Number
Model Code
to select
NSC30UD1 A 27
NSC40UD1 A-31
NST45UD1 A-39
NST70UD1 A-68
NSC30UD & NST30UD PL22
NSR17CS CS17
Figure 3
UP
button
Display
SET
button
DOWN 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 SET
button until the display changes, and repeat until a model code
appears.
8. Use the UP (
) or DOWN (–) buttons to select the correct model
code for your softener (see table below).
Figure 1
Position markers
(valve in service)
CAM
MOTOR
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 board
(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 water softener’s power supply from
electrical power
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.
3/4” Valve
1” Valve
MOTOR
CAM
Position markers
(valve in service)
RECHARGE
button
