WARNING: Inspection, testing and repair of electrical equipment should only be performed by a qualified service techni-
cian. Many of the tests require that the unit have power to it and live electrical components be exposed.
USE EXTREME CAUTION WHEN TESTING THE MACHINE.
TROUBLESHOOTING SECTION
16
Possible Cause Action
Defective thermostat.
If wash tank temperature is greater than 170
F (76.67 C), back thermostat CCW one full
turn and restart unit. When cycle completes,
set thermostat to 170 F (76.67 C) by turning
CW.
Leak in wash tank heating coil, allowing hot
recirculating system water to enter tank.
Empty wash tank and observe coils with
recirculating system on.
New control board placed into system and
not calibrated.
Perform auto-calibration.
Power to control board interrupted.
Check +12 VDC to control board (Voltage
should be between 10.8 and 14.4 VDC).
Make sure the transformer in main control
box is energized.
CAUTION: REVERSE
POLARITY WILL DAMAGE THE CIRCUIT
BOARDS.
Circuit chip (microprocessor) pins not fully
inserted into its sockets.
Check for bent pins. Ensure chip fully
inserted by gently pressing with thumb.
T-mid thermistor reading incorrectly. (May
be sensing non-existing high temperature.)
Check T-mid voltage reading at test points
on control board.
Ignition relay on control board inoperative.
Place finger on ignition relay and turn power
on. Should hear or feel the relay actuating.
If not, check circuit chip (microprocessor)
fully inserted. If so, replace control board.
Voltage not being sent from control board to
DSI.
Check for 12 VDC at black wire going from
control board to DSI. Ensure green wire on
DSI cable is grounded.
ECO defective or not electrically connected.
Check blue wire from DSI connected to one
spade terminal of ECO and another blue
wire connected from other spade terminal of
ECO and to the combination gas cutoff
valve.
Green LED flashes, but no ignition. (Igniter
sparks, no gas)
Green LED flashes, but no ignition attempt
(no igniter, no gas).
Symptom
High wash tank temperature.
No Green LED flash and the recirculating
pump is running or the Green LED stays on,
but does not flash.