101
XII. Troubleshooting
WARNING
Electrical Shock Hazard. Turn off power to boiler before working on wiring.
Condition
Possible Cause
Boiler not responding to call for heat, “Status” and
“Priority” show “Standby”.
Boiler is not seeing call for heat. Check thermostat or zone wiring for loose connection,
miswiring, or defective thermostat/zone control.
Boiler not responding to a call for heat, “Status”
shows “Standby” and “Priority” shows Central Heat
or Domestic Hot Water.
Boiler is not firing, temperature is greater than setpoint. Water flow through boiler primary
loop non-existent or too low.
Boiler Running but System or Boiler Circulator
is not running
• Check wiring for loose connection, miswiring. Flow switch is defective and needs
replacement.
• When there is a Domestic Hot Water Heat Request the System or Boiler pumps will be
forced “off” when there “Run Pump for” parameter is set to “Central heat, off DHW
demand” or “Central Heat, Optional Priority”. This has been set to allow all of the heat
to be provided for fast indirect water heater recovery. After one hour of “priority
protection” or the end of the Domestic Hot Water Heat Request the system and boiler
pumps will be free to run.
Home is cold during mild weather days
• Increase Low Boiler Water Temperature parameter 5°F (2.8°C) per day.
Home is cold during cold weather days
• Increase High Boiler Water Temperature parameter 5°F (2.8°C) per day
A. Troubleshooting problems where no error code is displayed.
Faults are investigated by selecting the “Help” button from the “Home” screen. When a fault is active the “Help” button flashes
and the home screen turns a red color. Continue to select flashing buttons to be directed to the Fault cause.
B. Display Faults:
Figure 43: Help Menu
Indication
Condition
Possible Cause
Display Completely Dark
Fan off, LWCO lights off, no green power
light on Control
No 120 VAC
Power at Boiler
Check breaker and wiring between breaker panel and boiler.
Display Completely Dark, Fan running
No 24 VAC
Power to Control
- Loose/defective 120Vac connection wiring between boiler J-Box and
transformer and/or transformer and Control.
- Loose 24 Vac connection wiring between transformer and Control.
Blinking Green power light on Control
Control
Fault
- The green light is connected to internal power supply. The power supply
is repeatedly starting and stopping (not normal) making the light flash. The
microprocessors are not running.
- Try disconnecting all terminals except 24VAC to power the Control. The
green light should be steady. If it is not then the control is defective. If
steady, start plugging in all the connectors while watching the green light.
When faulty wiring reconnected green light will begin to flash.
Display Completely Dark but Boiler fires
No 5 VDC
Power to Display
- Loose 5 VDC connection wiring between display and Control
- Defective display.
Display lost
communication
with control
- Loose or defective display harness
- Defective Display
- Defective Control
ER0011
Adjustment Mode
Password Timeout
- The Control and Display are
NOT
defective. The password has timed out.
Simply cycle power to the Display to restore operation.
Boiler
Energy Save On
Max Efficiency On
Standby
i
Status
Help
Adjust
Detail
Lockout
History
Service
Contract
Boiler Size
Setup
Sequencer
Setup
Active Faults
i
**00FF
Communication
Fault
i
Limit String
Status
Rate Limit
Status
Reset
Sensor
Status
Soft Lockout
(Hold)
Hard
Lockout
024
F
Sensor
Fault
Help Screen
Active Fault Screen
Home Screen
Summary of Contents for APEX
Page 57: ...57 VIII Electrical continued Figure 26 Ladder Diagram ...
Page 58: ...58 VIII Electrical continued ...
Page 59: ...59 Figure 27 Wiring Connections Diagram VIII Electrical continued ...
Page 105: ...105 ...
Page 109: ...109 XIII Repair Parts continued APX625 APX725 and APX825 APX825 shown ...
Page 112: ...112 XIII Repair Parts continued APX425 and APX525 ...
Page 114: ...114 XIII Repair Parts continued APX625 APX725 and APX825 ...
Page 122: ...122 ...
Page 123: ...123 ...
