Lochinvar 801, 400 service manual Outlet Arhl, Outlet Mrhl

Service Manual

3 Troubleshooting

Table 3-4(continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Boiler Interface

FAULT	DESCRIPTION		CORRECTIVE ACTION
		• Adjust the set point of the auto reset limit to a higher
		setting up to a maximum of 200°F. Reference the
		Knight XL Installation and Operation Manual for
		adjusting procedures.
		• 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	XL	Installation	and	Operation	Manual
		for the proper piping methods for the Knight XL boiler.
		• Check 120 vac to boiler pump motor on a call for
		heat. If voltage is not present, check wiring back to
	The outlet water temperature has exceeded	the main control board.
Outlet ARHL		• Replace the main control board if necessary.
	the setting of the automatic reset high limit.	• If 120 vac is present on a call for heat and the boiler
		pump is not operating, replace the pump.
		• 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 3-2A on page 35 of this manual. Replace
		sensor if necessary.
		• Replace high limit.
		• Adjust the set point of the manual reset limit to a higher
		setting up to a maximum of 210°F. Reference the
Outlet MRHL		Knight XL Installation and Operation Manual for
		adjusting procedures.
(will require a manual		• Verify that the system is full of water and that all air
reset once the condition	The outlet water temperature has exceeded	has been properly purged from the system.
has been corrected.		• Verify that the boiler is piped properly into the heating
Press the RESET	the setting of the manual reset high limit.	system.	Refer to Section 6 - Hydronic Piping of the
button on the SMART
SYSTEM display to		Knight	XL	Installation	and	Operation	Manual
		for the proper piping methods for the Knight XL boiler.
reset.)
		• 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.

40