Adjustable High, Limit w/Manual, Fan Low

Lochinvar 399 - 800 service manual Adjustable High, Limit w/Manual, Fan Low, Fan Speed Low

Page 35

Service Manual

3Troubleshooting (continued)

Table 3F (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Boiler Interface

FAULT	DESCRIPTION		CORRECTIVE ACTION

	The outlet water temperature has exceeded	• Verify that the system is full of water and that all air
	the setting of the high limit.	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	XL	Installation		and Operation		Manual
		for the proper piping methods for the Knight XL.
		• Check voltage to boiler pump motor on a call for
		heat. If voltage is not present, check wiring back to
Adjustable High		the pump relay.
Adjustable High		• Replace the pump relay if necessary.
Limit w/Manual		• Replace the pump relay if necessary.
Limit w/Manual
Reset		• If 120 VAC is present on a call for heat and the boiler
(will require a manual		pump is not operating, replace the pump.
reset once the condition		• If the system pump is a variable speed pump, ensure
has been corrected. Press		• If the system pump is a variable speed pump, ensure
has been corrected. Press		that the system flow is not less than the boiler flow.
the RESET button on the		that the system flow is not less than the boiler flow.
the RESET button on the		• If operating on either an inlet or system supply sensor,
SMART SYSTEM display		• If operating on either an inlet or system supply sensor,
SMART SYSTEM display		check temperature setting of the main control board.
to reset.)		check temperature setting of the main control board.
to reset.)
		• If the high limit has tripped, check setting of the
		device.
		• Check resistance of water sensors and compare to
		Table 3B on page 30 of this manual. Replace sensor
		if necessary.
		• Replace high limit.

	The actual fan RPM is 30% lower than what	• Vent/air intake lengths exceed the maximum allowed
	is being called for.	lengths. Refer to Section 3 - General Venting of the
		lengths. Refer to Section 3 - General Venting of the
Fan Low		Knight	XL	Installation	and Operation		Manual for
Fan Low		proper lengths.
OR		proper lengths.
OR
Fan Speed Low		• Check	for	obstruction	or	blockage in	the	vent/air
(will require a manual		• Check	for	obstruction	or	blockage in	the	vent/air
(will require a manual		intake pipes or at terminations.
reset once the condition		intake pipes or at terminations.
reset once the condition
has been corrected. Press		• Check the wiring connections at the fan and at the
the RESET button on the		• Check the wiring connections at the fan and at the
the RESET button on the		main control board.
SMART SYSTEM display		main control board.
SMART SYSTEM display
to reset.)		• Replace the fan.
		• Replace the fan.
		• Replace the main control board.

	Blown fuse.	• Replace fuse F4 on the control board, see page 28 of
		this manual.

Image 35

Contents

Models 399 Contents Niosh stated First Aid Please read before proceedingHandling ceramic fiber materials When servicing boiler Troubleshooting What is in this manual?Service MaintenanceNear boiler piping ServiceMenu / Exit UP Down Knight XL displayControl inputs Control outputs Smart Control ModuleSequence of operation General OperationHow the boiler operates How the control module operatesBLR Ignition Sequence of operationBLR SH 41% Rate Use this procedure to access menus from the display panel Display panel menu accessValue will appear Display panel parameter accessParameter table Temperature DataControl Circulation Service Viewable and changeable control parameters Temperature settingsFunctions DHW settingsOutdoor air reset Data loggingMinimum SH set point Maximum air temperatureShift reset curve Maximum SH set pointAnti-cycling Boiler cascade address Control modesSH controlling sensor SH sourceCirculation pumps Service NotificationCascade offset Owner maintenance Maintenance Maintenance and annual startupService technician Maintenance Check boiler relief valve Flue vent system and air pipingCheck water system Check expansion tankInspect ignition and flame sense electrodes Check ignition ground wiringCheck all boiler wiring Check control settingsReview with owner Check flame signalCleaning boiler heat exchanger Check the following TroubleshootingBefore troubleshooting Check control module fusesUnit Does Not No DisplayNo Burner OperationTemperature Resistance Checking temperature sensors System Pump Noisy No Pump Operation Boiler PumpSequence Switch/LWCOFlow FlameNo Flame Ign Anti-cyclingRunning No FlameFan Speed Low Adjustable HighLimit w/Manual Fan LowSensor Shorted Fan HighFan Speed High Sensor OpenTemp O/Shoot Open Rem Ctrl FltParameters ProgrLow 24 VAC Service BlkWatch Dog Error No Error StoredGas Supply Pressure Combustion Analysis ProcedureGas Valve Adjustment Or ObstructionModels 600 Gas valve adjustment procedureModel Page Page KBX-SER Rev E

Related manuals

Lochinvar 399 - 800 service manual Adjustable High, Limit w/Manual, Fan Low, Fan Speed Low

3Troubleshooting (continued)

FAULT

Adjustable High

Limit w/Manual

Reset

that the system flow is not less than the boiler flow.

Fan Low

Fan Speed Low