Gasmaster GMI 2M, Installation, Operation And Maintenance Manual

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IOM GMI 2M & 2ML Nov 2010.doc
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B: Sequence of Events
I:
Every boiler/water heater is fully tested at the factory prior to shipment. When the
unit is tested at the factory, a “jumper” is placed between terminals identified as
“Remote Enable/Disable” (see Figure 2). If BMS is used, this jumper should be
replaced by wires from the BMS. In the absence of a BMS, the operation of the
unit is governed by the Omron temperature controller.
II:
Once the blower starts operating, the air pressure switch will close. This switch has
been factory adjusted such that when the blower reaches its minimum frequency it
will close.
3.1.2 Pre-Purge
I:
When the air pressure switch is closed and safety loop is satisfied, pre-purge will
start.
II:
Blower continues to run at its maximum frequency for a period identified as the
purge time.
3.1.3 Pilot Flame
I:
After completion of the pre-purge period, the burner controller sends the required
voltage to the ignition rod, and 120V to the two, pilot safety shut off valves. The
valves open simultaneously with the activation of the ignition rod. Upon pilot
ignition, and after the flame is detected by the sensor, the ignition rod will be
deactivated.
II:
If after 5 seconds activation of the flame rod and opening of the gas valves, pilot
flame is not established and detected by the flame sensor, the gas valves will
immediately shut down and the boiler/water heater goes into the “lock-out” mode.
The unit will not re-start until the burner controller is manually reset.
WARNING
Do not bypass any of the instruments in the safety loop. Doing so
may cause serious damage to the unit and its surroundings.