Crest Audio FBN0751 Service Manual page 40

3
Troubleshooting
Table 3F Troubleshooting Chart - Noisy System
FAULT
- Supply gas problem. Natural and LP gas
pressures should be between 4 inches w.c.
(1.0 kPa) and 14 inches w.c. (3.5 kPa).
- Gas/air mixture problem.
Noisy
Operation
- Dirty/damaged burner.
- Air in the piping system.
- Blown fuse.
No Pump
Operation - - Faulty pump.
Boiler Pump
System Pump
- Internal fault on control board.
or
HWG Pump
- Faulty pump relay.
- Incorrect parameter setting.
- System pressure exceeds relief valve
setting.
Relief Valve
Opening
40
CAUSE CORRECTIVE ACTION
• Refer to Section 6 - Gas Connections of the Crest
Installation and Operation Manual for detailed
information concerning the gas supply.
• Refer to the Gas Valve Adjustment Procedure on
page 53 of this manual for the proper gas valve setting.
Verify that the vent/air intake lengths do not exceed the
maximum listed in the General Venting section of the
Crest Installation and Operation Manual.
• Refer to page 34 in this manual for the burner removal
and inspection procedure. Clean or replace the burner
as necessary.
• Properly purge all air from the piping system.
• Replace fuse F4 on the control board, see page 37 of
this manual.
• Replace pump.
• Replace main control board.
• Replace relay.
• Reference the Boiler Pump Mode and System
Pump Mode parameters in the Service section of this
manual.
• Lower the system pressure below the rating of
the supplied relief valve or replace the standard relief
valve with a higher rated valve up to the maximum
pressure of the heat exchanger 160 psi (40 kPa).
• Improperly sized expansion tank.
Service Manual