Document mbaNR3xENvVyRv1zoaKEaDyXQ
482 '
___________
y - CHAPTER 26
Table 2. Constants for Determining, the Capacity of BIow-Through Type Unit Heaters for Various Steam Pressures
. and Temperatures of Entering Air-
,
(Based on Steam Pressure of 8 psig and Entering Air Temperature of 60 F)
, Steam Pressure
.0
- -10 1.538
2 1,585
. 5
1.640
10 1.730
" i5;:
. 1.799
20s - .1,861
30''
1.966
; 40 2.058
' .50
2.134
.60 2.196
70 ,2.256
75 .2.283
. 80 .. . oo;
2.312 ; 2.36i
2.409
1.446
10 1.369
1,495 1.405
1.550 1.456
1.639 1.545
1.708. 1.614
1.769 1.675
1.871 1.775
1.959 1.862 .
2.035 T. 936,
2.094 1.997-
2.157 2.057
2.183 2.085
2.211 2.112
2.258 2.159;-.
2.307 . 2.204-
Temperature of Entering Air
20 1.273
30
1.191
. 40
1.110
1.320 1.237 11155
1.370 1.289 1.206
1.460 1-375 . 1.290
1.525 1.441 1.335
1.584 1.498 . 1.416
1.684 - T597 1.509
i.771; 1.683. 1.596
1.845. 1.755' .1.666
1.902 1.811 1.725
1.961 1.872 1.782
1.990 1.896 1.808
2.015 1.925 1.836
2.063 1.968 , 1.880
2.108.. .. 2.015 1.927
60 . 1.034
60 0.956
1.078 1.000
1.127 1,050
1.211 i.131
1.275 1,194
1.333 1.251
1.429 1.346
1.511 1.430
1.582 1.498.
1.640 .1.555
1.696 1.610
1.721 , 1.635
1.748 1.660;.
' 1.792 1,705
. 1.836 1.749 .
70 '
0.881.' 0.926 0.974 1.056 1.117 1,174 1.266. 1.3491.416 1,472 1.527 1.552 1.577; 1.621' 1.663
80
0:809 0.853 0.901 0.982 1.043 1.097 1.190 1.270 1.338 1.393 1.447 1.472 1.497 1.541 1.581
60
0.739
100, 0.671
0.782 0.713 -
0.829 0.760
0.908 . 0.838
0.970 0.897
1.024 0.952
.1.115 1.042
1.194 1.1-19 "
1.262 ' 1,187
1.314 1.239
1.368 1.293
1.392 1.316
1.418 1.342
1.461 1.383
. 1.502 1.424
. . o
Note: To determine capacity at any steam pressure and entering temperature, multiply constant from table by rated capacity at 00 F entering air and 2 pal/ outlet temperature^lTStfafa^tory ^ ^ *mportant to determine whether the heater la suitable for the Increased pressure application and whether the resulting Increased
' - 1946 G u id e
T ' U n it H eaters,'U nit Ventilators, U n it H um idifiers
Table 3. Constants for Determining the Capacity of Dkiw-Through Type Unit Heaters for Various Steam Pressures
and Temperatures of Entering Air
(Based on Steam Pressure of 8 psig and Entering Air Temperature of 60 F)
Stiam Pbessurb psi . -
.0
'
"10 .
1.483.:
' 0 1.405
' 1^ . 1.329,
20
1.253
2 1.520 1.442 1.363' 1.290
.5 1.565. 1.485 .1.410 1.334
10 ,1:637 1.558 1.480 . 1.403
15 1,688- . 1.610 ; 1.533 1.458
20 . . 1,728.. .1,649 1.572. , 1.498
30 i.803, 1.725 ; 1.648 1.572
. 40 50
1.864 1,787, ,1.710 1.927 , i. 850 . 1-773
1.637 1.700
.60
1.973 1.897 .1.820 1.748
70 2.018 . 1.943 1:869 1.795
.75
2.043 1.970 1.895 1.822
80 2.064 1.988 -. 1.914 1.841
90 -
2.102
2.028
1.951
1.878
' . 100
2.150 2.071 1.994 1.919
. 30 1.178 1.215 1.260 1.328 1.382, '1.421 - 1.497 1.563 1,628 1.673 1.722 1.750 1.770 1.804 1.845
Tbmpbratuhb op Entering Am
40
1.105
50?
1-.032
60 ,
0.962
1,141. 1.069 1,000
1.187 1.114 1.045
,1.253 . 1.182 1.112
1.310 1.239 1.168
1.350 1.278 1.208
1.423 . 1.352 1.281-
. 1.491 .1.420 1.350
1.554 1.483 1.416
1.601 1.531 : 1;463
1.651 . 1.582 1.512
1.680. 1.609 1.540
1.698 1.629 1.560
1.732 1.661 . 1.590
1.770 1.700 . .1.630
'70 0.892
$0
0.822
0.930 0.861
0.975 0.906
1.042 0.973
1.099 1,028
1.138 . 1.070
1.212
1.145
1.282 1.215
1.347 . 1.278
1.394 . 1.325
1.443 1.377
1.471 1.402
1.491 1.422
i .523 1.457
1.560 1.492
90
0.754
ioo*
0:688
- 0.792 0.728 -
0.838 0:771 .
0.903 0.838 ;
0.960 0.895
1.002 1.078 1.148
01936.
.1 -010 '
l.osi :
1.211
l"l45 .
1.260 1.194
1.310 1:243
1.333. 1.268
1.354 1.288
1.387 1.321.
1.425.. 1.359
Note: To determine capacity at any steam pressure and entering temperature, multiply constant from table by rated capacity at 00 F entering air and 2 psi.
When Increasing steam pressure it is important to determine whether the heater is suitable for the increased pressure application and whether the resulting increased
, outlet temperature is satisfactory.
-
^
^
:\