Milnor 7272TG1L, Установка и обслуживание

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Gas and Air Adjustments
PELLERIN MILNOR CORPORATION
3.10.
Step 8 Setting Low Gas Pressure Switch
Note 12:
Set a replacement low gas pressure switch to the lowest value before installing, then adjust as
below.
1. Connect one side of manometer (high pressure side of differential pressure gauge) to X
( Figure 1 and Figure 2 ); leave the other side open to atmosphere.
2. Start with the external gas shut-off valve open, and close it slowly until the value shown in
Table 2 or Table 3 is read on the manometer. Set the low gas pressure switch dial to the
highest value. Slowly turn dial until the switch trips,
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status light illuminates
MOMENTARILY, and the burner extinguishes. Verify the setting by opening the external
gas shut-off valve fully, then closing the valve while watching the manometer. The low gas
pressure switch should trip when the set value is reached.
3. Open external gas shut-off valve FULLY.
3.11.
Step 9: Setting the Burner Pressure Switch
1. Set modulating gas valve position to 000 (minimum fire).
2. Attach the low pressure side of the manometer to the plenum air gauge point (item 2, Figure
10 ) and leave the other side open to the atmosphere.
3. Remove the switch cover and carefully turn the 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 CW until the burner indicator light (item 4, Figure 10 )
is on and the burner extinguishes.
6. Close the needle valve(s) fully.
3.12.
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.
4.
Adjustments for Propane-fired Dryers
Propane has a much higher caloric content per unit volume than natural gas. This can cause the
burner to roar if the
On-Off valve is adjusted for natural gas when the dryer is fueled with
propane. Perform this procedure to adjust the On-Off valve for proper operation with propane.
1. As detailed in Section 3.7 (CSA models), set the modulating valve position to MVP=100 and
verify that the regulated main gas pressure is 6.5 inches (165mm) water column.
2. Connect a manometer between the burner gas pipe and the burner box plenum reference
point, as shown in Figure 11 .
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