UTICA BOILERS UB90-200 Installation, Operation & Maintenance Manual page 24

If burner appears to pulsate during ignition:
Turn off boiler power and shut off gas supply to the boiler.
1.
Take the burner assembly apart by removing the combustion air blower and gas valve/
2.
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.
Reassemble burner assembly, turn gas supply and boiler power back on, and relight
3.
boiler.
If burner still pulsates or fails to light:
Check for proper vent and intake pipe sizing and for proper vent lengths and vent
1.
confi guration by referring to, "before installing the boiler," and "combustion air and vent
pipe," sections in this manual.
Check for proper gas supply pressure and proper gas line sizing to the boiler by referring
2.
to, "gas supply piping," section in this manual.
Check for orifi ce in negative pressure hose at gas valve and 2" air intake pipe upstream of
3.
gas valve.
Relight boiler.
4.
If boiler still does not light, the air inlet pipe may need to be disconnected to allow the
5.
boiler to start in order to verify the boiler fi ring rate and combustion properties. The inlet
air pipe can be disconnected by removing the pvc inlet air piping from the Fernco fi tting
located on the air inlet of the gas valve/venturi assembly. Relight boiler.
When the boiler lights, the fi ring rate and combustion should be checked per the
6.
"adjustments and checkout" procedure section of this manual. If the air inlet piping was
disconnected in step 4 (above), leave it disconnected and make fi rst adjustment. Then
reconnect air inlet piping, recheck combustion CO
If burner pulsation continues or boiler fails to light after performing the above procedures,
7.
please contact technical service at 1-800-325-5479 for further assistance.
STARTUP
NOTICE
, and adjust again if necessary.
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