Lochinvar 50-210 Troubleshooting continued, Fault, Description, Corrective Action, Auto Reset

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 fixed setting of the automatic reset high	has been properly purged from the system.
	limit or the setting of an optional manual	• Verify that the boiler is piped properly into the heating
	reset high limit.	system. Refer to Section 6 - Hydronic Piping of the
		Knight Wall Mount Installation and Operation Manual
		for the proper piping methods for the Knight wall
		mount.
		• Check 120 vac to boiler pump motor on a call for
		heat. If voltage is not present, check wiring back to
		the main control board.
		• Replace the main control board if necessary.
Auto Reset		• If 120 vac is present on a call for heat and the boiler
		pump is not operating, replace the pump.
High Limit
		• If the system pump is a variable speed pump, ensure
		that the system flow is not less than the boiler flow.
		• If operating on something other than an outlet sensor,
		check temperature setting of the main control board.
		• If the optional manual reset 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
Fan Low		Knight Wall Mount Installation and Operation Manual
		for proper lengths.
OR
Fan Speed Low		• Check for obstruction or blockage in the vent/air
(will require a manual
		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
		main control board.
SMART SYSTEM display
to reset.)		• Replace the fan.
		• Replace the main control board.
	Blown fuse.	• Replace fuse F4 on the control board, see page 28 of
		this manual.

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