74 “Translation of the original instruction”
6.8 Electrical Fault Diagnosis
Fault Description Method to repair
The pump works only in one
direction
Control coil failure (EDC)
Measure the coil resistance, its
resistance value should be
14.20 ohms
(24V) or 3.66 ohms (12V) at 20 degrees
Celsius (70 degrees Fahrenheit). Replace
the coil.
The controller is not available with electric
power
Restore power to the controller
normally
Poor electrical contact with the pump Disconnect, check the line, reconnect the
wires
Filter bypass indicator switch The switch may be damaged Check / replace the switch. Measure the
bypass port pressure to determine the
appropriate flow. Determine the switch
operation b
y measuring the resistance.
Open: resistance greater than or equal to
510ohms; closed: resistance is less than
or equal to 122ohms.