Milnor 6464TG1L, Руководство по установке, Страница: 73 / 85

Pellerin Milnor Corporation
4. Return to minimum fire (MVP = 001) and main air damper position 2 (D = 2).
5. Confirm that the pressure is within the range specified in
Table 3, page 2 . If not, see below
notice.
NOTICE:
Insufficient combustion air—If you measured insufficient differential pres-
sure, go no further. There is a problem with the combustion air supply, perhaps with the
combustion air motor or the ratio air actuator. You will not be able to complete the adjust-
ment steps.
• Troubleshoot then restart the adjustment steps.
7.7. Step 7: Set the maximum fire differential gas pressure
BNDGUM02.T07 0000342546 B.2 A.4 5/13/21 8:47 AM Released
1. See Figure 1, page 4 . Connect the manometer across
GFH
and
GFL
.
2. Loosen the locking screw (item 4) on
VB
.
3. See caution statement above and Section 6 , page 7 . Command maximum fire (MVP = 255)
and main air damper fully open (D = 0).
4. Take note of the manometer pressure reading.
5. Command minimum fire (MVP = 001) and main air damper position 2 (D = 2).
6. In Step 1, you set the manual butterfly valve fully open. On any 64_TG1 model, confirm that
the differential pressure is within or above the range given in Table 3, page 2 . If not, see be-
low notice. On any 76_TG1 or 82_TG1 model, record the value read on the manometer and
continue.
7. On any 64_TG1 model, if the measured pressure is
above
the specified range, command max-
imum fire (MVP = 255) and main air damper fully open (D = 0). Adjust VB until the differen-
tial pressure is within the acceptable range specified in Table 3, page 2 .
8. On any 76_TG1 or 82_TG1 model, command maximum fire (MVP = 255) and main air
damper fully open (D = 0). Attempt to adjust VB until the differential pressure is within the
acceptable range specified in Table 3, page 2 . If it is not possible to achieve the acceptable
range, see the below notice.
9. Command minimum fire (MVP = 001) and main air damper position 2 (D = 2).
10. Tighten the locking screw (item 4) on
VB
.
NOTICE:
Insufficient gas pressure.—If the differential gas pressure is below the range
given in Table 3, page 2 with the butterfly valve fully open, go no further. There is a prob-
lem with the gas supply. It will not be possible to make the subsequent adjustments.
• On any 64_TG1 model, troubleshoot then restart the adjustment steps. If the differential pres-
sure is close to the required range, you can open the ratio regulator (RR in Figure 2, page 5 )
an additional amount, not to exceed 2 additional turns. On any 76_TG1 or 82_TG1 model,
contact the Milnor factory for assistance. You may need to provide the value recorded in Step
6, above.
Set the Heating System—Ratio Air Dryer
69