Lochinvar CREST 3 - Manual (Page 48)

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