Operating Your Boiler - UTICA BOILERS MGC 3 Series Installation, Operation & Maintenance Manual

AUTOMATIC GAS VALVE
Automatic Gas Valve opens or closes according to heat
requirements of thermostat and temperature limit control.
It closes if pilot goes out. Each individual control must be
operating correctly before any gas can pass to burners. Any
one control can hold gas supply from burner regardless of
demand of any other control.
SAFETY PILOT
Safety Pilot prevents flow of gas to burner if pilot goes out,
or will not ignite.
GAS VALVE SAFETY SHUTDOWN TEST
Ignition system safety shutoff device must be tested after
placing boiler in operation.
RELIGHT
Electric and gas shall be off for 5 minutes before relighting.
THERMOSTAT
Keep it set at desired room temperature. If windows are to
be opened or heat is not needed, move thermostat pointer
to lower setting.
NOTICE
In event of failure of any component, system will
not operate or will go into safety lockout. System
is completely self-checking. On every call for heat,
each component must be functioning properly to
permit operation. Safety lockout system has to be
reset by turning thermostat to lowest setting for
one minute, then back to normal setting.
ADJUST PILOT BURNER
Pilot flame should surround 3/8" to 1/2" of the pilot sensor.
See Figure 14. If flame needs adjusting, do it as follows:
1.
Remove screw cover over pilot adjusting screw.
2. Insert small screwdriver and adjust flame as needed.
Turn screw counterclockwise to increase flame, clockwise
to decrease.
3. Replace screw cover over pilot adjusting screw.

13 - OPERATING YOUR BOILER

Figure 14 - Pilot Flame
MAIN BURNER(S)
• Main burners do not require primary air adjustment and
• Main burner flames form sharp blue inner cones in softer
• Puffs of air from blowing on flame or stamping on floor
• If flame appearance is not correct, check main burner
Figure 15 - Burner
ADJUST LIMIT CONTROLS
Instructions for each control are included with controls.
Settings can be changed. Refer to Appendix A page 29 for
information.
23
are not equipped with primary air shutters.
blue outer mantel, with no yellow.
will cause flames to turn orange momentarily. This is
not unusual. Remain still when observing main burner
flames.
orifices, burner throat and flame ports for dust and
lint obstruction. It may be necessary to remove rollout
shield to observe main burner flames. Replace rollout
shield after observation. Refer to Figure 15.
PN 240013087 Rev. A [09/30/2020]