AmeriWater MRO2X, Operation & Maintenance Manual

Page: 47 / 55

MRO2X
– 5X Manual
- 43 -
98-0058
Rev. R
9.2 CONTROLLER TROUBLESHOOTING
CAUTION: Hazardous voltages are present when power is applied to the unit. Care
should be taken when troubleshooting any of the input power or output
circuits. When disconnecting or connecting any board or accessory, be
sure power is unplugged.
Before contacting AmeriWater for technical help, verify the programming of all Setpoints, check
the display and check the status of all lights and indicators. The more information available
when you contact us, the easier it will be to determine the source of the problem. Standard
setpoints, and drawings of the controller and pc boards can be found in Section 6.
PROBLEM
INVESTIGATION CORRECTIVE ACTION
System Inoperative Is the yellow CPU active LED
blinking?
If no, is the green power
LED, DS1 Lit?
If no, is the fuse OK?
If no, replace the fuse.
If yes, with a voltmeter, verify
power is applied to the power
terminals L1 and L2.
If power is applied to the
power terminals and the
other checks are OK, the pc
board is defective and should
be replaced.
If no power is applied to the
board, check the power
wiring to the system.
Display Blank Is the green power LED, DS1
lit?
If yes, is the CPU active LED,
DS9 blinking?
If yes, adjust the display
contrast adjustment, R3. Is
the display still blank?
If no, refer to the system
inoperative section.
If no, replace the board.
If yes, replace the board.
Inlet Valve Will Not Operate Is the system in standby?
If no, are any shut down
conditions active?
If no, is the inlet LED, DS8
lit?
If yes, with a voltmeter, verify
if there is power on the inlet
terminals. Is there power?
If no, replace the board.
If no, replace the board.
If yes, check the valve and
wiring.