Milnor 7272TG1L, Installation And Service

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Gas and Air Adjustments
PELLERIN MILNOR CORPORATION
3. Remove the switch cover and carefully turn white potentiometer CCW until the threaded
adjuster is level with the adjustment collar. Do not back the adjustment screw out completely
as the adjustment screw is spring loaded.
4. Adjust the plenum reference point needle valve (item 1, Figure 10 ) until the manometer
achieves the value shown on Table 2 or Table 3.
5. Slowly turn the burner pressure switch potentiometer CW until the burner indicator light
(item 4, Figure 10 ) is on and the burner extinguishes.
6. Close the needle valve(s) fully.
2.13.
Step 10: Setting the Back Pressure Switch
1. The back pressure switch dial is factory set, but may have to be adjusted slightly once the
machine is connected to the laundry ductwork.
2. Attach the low pressure side of the manometer to the bottom of the needle valve gauge point
(next to the back pressure switch Figure 8 ); leave the other side open to the atmosphere.
3. Adjust the needle valve until the manometer achieves the value shown on Table 2 or Table 3.
4. Slowly turn dial until the screen displays a “clean the lint screen,” message.
5. Close the needle valve fully.
3.
Adjustment Procedures for Landis and Gyr Equipped Dryers
3.1.
Step 1 Setting Static Gas Pressure
WARNING 5 : Entangle and Crush Hazard
—Moving parts can entangle and crush
body parts
• Lock off and tag out power before servicing.
1. Turn machine off .
2. Attach one side of manometer (high pressure side of differential pressure gauge) to static gas
pressure gauge point (X); leave the other side open to atmosphere.
3. Open external gas shut-off valve.
4. Check the status of the following components
• External gas shut-off valve is open .
• Manual test valve and modulating gas valve are closed.
• Pilot and burner are not firing.
• Combustion air blower and main blower are off.
5. Adjust pressure of incoming gas (upstream from dryer) to achieve value listed in the Table 2
or Table 3 . Incoming gas pressure must be at this value before further adjustments can be
made. Pressures exceeding specified range will damage regulator.
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