TM 9-4120-402-14
5-36. BLAST DAMPER. - continued
(c) Reset open damper door (4).
(d) If damper door (4) did not trip with marker in green band range, adjust trip mechanism as follows:
1 Loosen nut (5) on spring adjusting screw (6).
2 If damper door (4) tripped before marker reached green color band, turn spring adjusting
screw (6) in (clockwise).
3 If damper door (4) tripped after marker passed green color band or not at all, turn spring
adjusting screw (6) out (counterclockwise).
4 Re-test blast damper as (b) above and reset open damper door (4). Continue adjusting
and testing as necessary.
5 Tighten nut (5) on spring adjusting screw (6) when adjustment is complete.
b. Inspect.
(1) Inspect fresh air cover (1) as follows: (See figure 5-32.)
(a) Check that cover (1) is not dented, cracked, or punctured. Replace if damaged.
(b) Check that gasket (2) is not tom, loose, or missing. Replace if damaged or missing.
Figure 5-32. Fresh Air Cover
(2) Inspect blast damper as follows:
(a) Check that filter is clean and in place. Clean if dirty. Replace if damaged or missing.
(b) Check that screen is clean and free of all blockages. Clean if dirty or blocked.
(c) Check that damper door is in the open position. Damper door is closed if reset lever is pointing
down, and open if reset lever is pointing away from unit about 45
.
(d) Check that all gaskets are not torn, loose, or missing. Replace if damaged or missing.
(e) Check that fabric panel is not torn, loose, or missing. Replace if damaged or missing.
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