UTICA BOILERS UB90125 Installation, Operation And Maintanance Manual page 25

iF BUrNer aPPears to PUlsate DUriNg
igNitioN:
1. Turn off boiler power and shut off gas supply to the boiler.
2. Take the burner assembly apart by removing the combus-
tion air blower and gas valve/venturi assembly from the
boiler and visually inspect the inside of the burner. Look for
any debris (PVC shavings, etc.) and if anything is present,
remove it.
3. Reassemble burner assembly, turn gas supply and boiler
power back on, and relight boiler.
iF BUrNer still PUlsates or Fails to ligHt:
1. Check for proper vent and intake pipe sizing and for proper
vent lengths and vent configuration by referring to, "Before
Installing The Boiler," and "Combustion Air and Vent Pipe,"
sections in this manual.
2. Check for proper gas supply pressure and proper gas line
sizing to the boiler by referring to, "Gas Supply Piping," sec-
tion in this manual.
3. Check for orifice in negative pressure hose at gas valve and
2" air intake pipe upstream of gas valve.
4. Relight boiler.
5. If boiler still does not light, the air inlet pipe may need to be
disconnected to allow the boiler to start in order to verify
the boiler firing rate and combustion properties. The inlet
air pipe can be disconnected by removing the PVC inlet air
piping from the Fernco fitting located on the air inlet of the
gas valve/venturi assembly. Relight boiler.
6. When the boiler lights, the firing rate and combustion should
be checked per the "Adjustments and Checkout" procedure
Section of this manual. If the air inlet piping was discon-
nected in step 4 (above), leave it disconnected and make
first adjustment. Then reconnect air inlet piping, recheck
combustion CO , and adjust again if necessary.
2
7. If burner pulsation continues or boiler fails to light after per-
forming the above procedures, please contact Technical
Service at 1-800-325-5479 for further assistance.
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