Milnor 7272TG1L, Установка и обслуживание

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Gas and Air Adjustments
PELLERIN MILNOR CORPORATION
2.3.
Step 2: Setting the Low Combustion Air Pressure Switch
Display or Action Explanation
SETUP PROCEDURE
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This step turns on the combustion air motor contactor. The
main air pressure switch, modulating gas valve and the two
main gas valves are disabled.
u
Accesses setup mode A
SETUP MODE A
SET COMBUSTION AIR
1. Mount the manometer horizontally as shown in Figure 5 .
2. Attach the low pressure side of the manometer to the plenum air gauge point (P, Figure 4 )
and attach the other side of the gauge to the combustion air gauge point (B) near the low
combustion air pressure switch (A).
3. Adjust the plenum reference point needle valve (G) until the manometer achieves the value
shown in Table 2 or Table 3 . If this value can't be obtained with the plenum reference
needle valve wide open, then slowly open the combustion air needle valve (C), until the
desired value is achieved.
4. Slowly rotate the low combustion air pressure switch dial until the
!
light is on .
5. Close the needle valve(s) fully.
2.4.
Step 3: Setting the Main Air Pressure Switch
Note 4: Adjust the main air pressure switch very slowly, allowing time for pressure to drop.
Note 5: Verify that the damper is fully open during step.
Display or Action Explanation
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Accesses setup mode B
SETUP MODE B
SET COMBUSTION AIR
1. Attach the low pressure side of the manometer to the main air pressure switch gauge point
(M, Figure 4 ), leave the other side open to the atmosphere.
2. Open the main air pressure needle valve (H, Figure 4 ) until the manometer is at the value
shown in Table 2 or Table 3 .
3. Slowly rotate the main air pressure switch dial (I, Figure 4 ) until the @ status light is on .
4. Close the needle valve fully.
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