Milnor 7272TG1L, Installation And Service

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Gas and Air Adjustments
PELLERIN MILNOR CORPORATION
1.3.
How the Landis & Gyr Flame Control Works
—After the dryer is loaded, the dryer
control sets the modulating gas valve to the minimum fire position and tells the flame control
that fire is desired. The flame control turns on the main and combustion air motor contactors ,
checks that all safety requirements are satisfied, then turns on the spark ignition and opens the
pilot gas valves . After the pilot valves are opened and the flame control receives an input from
the flame rod, it opens the two main gas valves . If the pilot flame or any safety is not satisfied,
the flame control locks out. The lock out trips the fire eye relay and illuminates the
%
status
light. Push either the
K
or the flame control reset and A to clear any error.
1.4.
Dryer Gas Train Components and Settings
—When testing and adjusting the gas
train, the technician will proceed through a sequence of steps, each containing various sub-steps.
During a typical step, the technician will perform the following general tasks:
• Measure the pressure differential between a specified gauge point and reference point.
• Adjust certain components to achieve the expected results.
1. Table 1 provides a quick reference to the steps, test locations, and component states for
Fireye equipped machines. Table 2 or Table 3 specifies the required values. The general steps
are the same for both types of flame controls.
2. See Section 2 “Adjustment Procedures for Fireye Equipped Dryers” for more details.
Although the major steps are the same for each type of flame control, the sub-steps vary
somewhat.
3. You will need to refer to both the summarized and the detailed information when testing and
adjusting the system.
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