Lochinvar KNIGHT 81-286 Service Manual page 45

3
Troubleshooting
Table 3-4 (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Boiler Interface
FAULT
Outlet Temp
High
Outlet water temperature has exceeded the
(continued)
maximum outlet water temperature.
External control is cycling too often.
Rem Ctrl Flt
Parameters
Progr
(will require a manual
reset once the condition
After downloading parameters from a laptop,
has been corrected. Press
the main control board must be reset.
the RESET button on the
SMART SYSTEM display
to reset.)
While the unit is in Service Mode, the outlet
temperature has exceeded 185°F.
Service Blk
(continued)
DESCRIPTION CORRECTIVE ACTION
• Verify that the boiler pump is set to the proper speed
or that the boiler pump is the proper size. Reference
Section 6 - Hydronic Piping of the Knight
Installation and Operation Manual for boiler pump
specifications.
• Replace the main control board.
• Check set point of the external control.
• Check the wiring between the external control and the
unit.
• Replace the control.
• Press the ENTER/RESET button on the SMART
SYSTEM display panel.
• Establish a heating load to remove the heat from the
boiler loop.
• Verify that the system is full of water and that all air
has been properly purged from the system.
• Verify that the boiler is piped properly into the heating
system. Refer to Section 6 - Hydronic Piping of the
Knight Boiler Installation
Manual for the proper piping methods for the Knight
boiler.
• Check 120 vac to the boiler pump motor on a call for
heat. If voltage is not present, check the wiring back
to the main control board. Replace the main control
board if necessary.
• If 120 vac is present on a call for heat and the boiler
pump is not operating, replace the pump.
• Verify that the boiler pump is set to the proper speed
or that the boiler pump is the proper size. Reference
Section 6 - Hydronic
Boiler Installation and Operation Manual for boiler
pump specifications.
Service Manual
Boiler
and Operation
Piping of the Knight
45