Nortec NHTC Humidifier User Manual


 
10-10
Page 15
2008-10-01
Table 3. Grains of Water Per Cubic Foot – Saturated Air (100% rh)
(2) Formula 2
Assume our printing plant is located in Denver, Colorado. From Table 4, the worst
case is -10
°F with 37% rh
From Table 3:
0.29 gr/ft
3
x 37% rh - 0.11 gr/ft
3
Combining this result with that of Moisture Required (A) we see that we will need
5.19 - 0.11 = 5.08 grains of moisture for every cubic foot of outside air brought in.
E. INCOMING AIR VOLUME
(1) The following outlines the steps necessary to determine the amount of outside air being
brought into the humidified space and the corresponding amount of moisture required.
There are three basic means by which outside air is introduced into the humidified
space. These are:
(a) Through natural ventilation, for example, opening and closing doors and windows,
and by infiltration through cracks and openings in the building construction.
(b) Through mechanical ventilation, for example, the introduction of make-up air, or
the exhausting of stale air by the building HVAC system.
(c) Through the economizer section of the HVAC system - if this feature is included in
the system.
(2) For maximum accuracy, all three should be estimated and the largest chosen.
°C °F Grains °C °F Grains °C °F Grains °C °F Grains °C °F Grains °C °F Grains
-23 -10 .29 4 40 2.86 58 5.41 76 9.75 35 95 17.28 114 29.34
-5 .35 41 2.97 59 5.60 77 10.06 96 17.80 115 30.13
-18 0 .48 42 3.08 16 60 5.80 78 10.40 97 18.31 49 120 34.38
8 .61 43 3.20 61 6.00 79 10.80 98 18.85 125 39.13
-12 10 .78 44 3.32 62 6.20 27 80 11.04 99 19.39 54 130 44.41
-9 15 .99 7 45 3.44 63 6.41 81 11.40 38 100 19.95 135 50.30
-7 20 1.24 46 3.56 64 6.62 82 11.75 101 20.52 60 140 56.81
-4 25 1.56 47 3.69 18 65 6.85 83 12.11 102 21.11 145 64.04
-1 30 1.95 48 3.83 66 7.07 84 12.49 103 21.71 66 150 72.00
31 2.04 49 3.97 67 7.31 29 85 12.87 104 22.32 155 80.77
32 2.13 10 50 4.11 68 7.57 86 13.27 41 105 22.95 71 160 90.43
33 2.21 51 4.26 69 7.80 87 13.67 106 23.60 165 101.00
34 2.29 52 4.41 21 70 8.10 88 14.08 107 24.26 77 170 112.60
2 35 2.38 53 4.56 71 8.32 89 14.51 108 24.93 175 125.40
36 2.47 54 4.72 72 8.59 32 90 14.94 109 25.62 82 180 139.20
37 2.56 13 55 4.89 73 8.87 91 15.39 43 110 26.34 185 154.30
38 2.66 56 5.06 74 9.15 92 15.84 111 27.07 88 190 170.70
39 2.76 57 5.23 24 75 9.45 93 16.31 112 27.81 195 188.60
94 16.79 113 28.57