Lochinvar CREST 3 - Manual (Page 50)

3
Troubleshooting
Table 3G (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Boiler Interface
FAULT DESCRIPTION CORRECTIVE ACTION
Too Many
Resets - Try Later
Too many manual resets have occurred
during a 15 minute period.
• Wait 15 minutes and try again.
• Turn power off to unit, wait 30 seconds and then turn
power back on.
Internal Fault
The main control board has detected an
internal fault.
• Replace the main control board.
Writing to
Memos
The main control board has detected an
internal fault.
• Replace the main control board.
Flue Temp
Shutdown
The stack temperature has exceeded the
set parameters for the boiler.
• Inspect the heat exchanger. Reference page 35 of
this manual for the procedure on how to clean the
flue side of the heat exchanger.
• Inspect the flue sensor and associated wiring.
Measure the resistance of the flue sensor and
compare to Table 3E on page 38 of this manual.
Replace the sensor if necessary.
• Verify that the vent/air intake pipes are properly
installed and that there are no obstructions.
• Replace the main control board.
Delta T
Shutdown
The temperature rise across the heat
exchanger has exceeded the set parameters
for the boiler.
• 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 5 - Hydronic Piping of the
Crest Installation and Operation Manual
for the proper piping methods for the Crest boiler.
• Check for voltage to the boiler pump motor on a call
for heat. If voltage is not present, check the wiring
back to the pump relay. Replace the pump relay if
necessary.
• If 120 VAC is present on a call for heat and the boiler
pump is not operating, replace the pump.
• Verify that the boiler pump is set to the proper speed
or that the pump is the proper size. Reference
Section 5 - Hydronic Piping of the Crest
Installation and Operation Manual for boiler
pump specifications.
Service Manual
50