Boiler User Manual

3 Troubleshooting
Table 3G (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Boiler Interface
FAULT DESCRIPTION CORRECTIVE ACTION
Sensor Open
(will require a manual
reset once the condition
has been corrected. Press
the RESET button on the
display to reset.)
Either the inlet water or outlet water
temperature sensor has been disconnected.
Check the sensors and their associated wiring.
Repair or replace the sensor or wiring if damaged.
Measure the resistance of the sensors and compare
the resistance to the tables on page 38 of this
manual.
Replace the sensor if necessary.
Sensor Shorted
(will require a manual
reset once the condition
has been corrected. Press
the RESET button on the
display to reset.)
Either the inlet water or outlet water
temperature sensor has been shorted.
Check the sensors and their associated wiring.
Repair or replace the sensor or wiring if damaged.
Measure the resistance of the sensors and compare
the resistance to the tables on page 38 of this
manual.
Replace the sensor if necessary.
Flue Sensor
Open
(will require a manual
reset once the condition
has been corrected. Press
the RESET button on the
display to reset.)
The flue sensor has been disconnected or
removed from the flue.
Check the sensor and its associated wiring. Repair
or replace the sensor or wiring if damaged.
Measure the resistance of the sensors and compare
the resistance to the tables on page 38 of this
manual.
Replace the sensor in flue.
Replace the sensor if necessary.
Flue Sensor
Shorted
(will require a manual
reset once the condition
has been corrected. Press
the RESET button on the
display to reset.)
The flue sensor has been shorted.
Check the sensor and its associated wiring. Repair
or replace the sensor or wiring if damaged.
Measure the resistance of the sensors and compare
the resistance to the tables on page 38 of this
manual.
Replace the sensor if necessary.
Tank Open
Sensors equipped with an internal limit (such
as the Lochinvar Squire
®
Indirect Tank), the
limit has opened due to temperature (195°F)
or the sensor has become disconnected.
Check the tank temperature.
Repair or replace the sensor wiring if damaged.
Replace the sensor if necessary.
Blower Proving
Switch Open 1
(will require a manual
reset once the condition
has been corrected. Press
the RESET button on the
display to reset.)
Blower proving pressure switch 1 contacts
are open.
Check the wiring connections to switch. Wires should
be connected to the common and normally open
terminals.
• Remove switch and check for blockage in the orifice.
Vent/air intake lengths exceed the maximum allowed
lengths. Refer to Section 2 - General Venting of the
Crest Installation and Operation Manual for
proper lengths.
Check for obstruction or blockage in the vent/air
intake pipes or at terminations.
• Inspect the burner. Reference page 34 of this manual
for removal and cleaning procedures. Replace if
necessary.
Verify combustion air blower 1 is operating. Replace if
necessary.
Inspect the heat exchanger. Reference page 35 of
this manual for removal and cleaning procedures.
Faulty pressure switch. Replace switch.
Service Manual
48