20
Heat Reclaim Coil Selection Example:
Select reclaim coil for Size 26 air handler at 13280 CFM,
344 MBH reclaimed at 45°F. Temperature Difference.
A. Change the application’s requirement at application’s TD
to adjusted requirement at 50°F. TD. Use Table 15:
344/0.9 = 382.2 MBH (adjusted)
B. Divide the adjusted MBH by the coil face area:
382.2 / 26.56 = 14.4 MBH (adjusted) per square foot
C. Find the coil air speed:
13280 / 26.56 = 500 fpm
D. Select coil rows and fins per inch from Table 16 at coil air
speed and with enough MBH to meet the MBH (adjusted to 50°F. TD) per square foot figured in step B:
Select 3 row 8 fin per inch coil with capacity of 14.56 MBH per square foot at 50°F. TD.
For this application, capacity equals: (14.56 x 26.56 x 0.9) or 348 MBH for size 26 at 45°F. TD.
E. When ordering, please specify refrigerant type and the total heat of rejection for each reclaim circuit.
Or specify the per cent of the total heat of rejection that is reclaimed for each circuit.
Table 15
Heat reclaim correction factor for temperature difference between air and refrigerant.
Temperature Difference
20
25
30
35
40
45
50
60
Correction Factor
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.2
This table for R-22, for R404A & R507, multiply MBH by 0.98
For heat reclaim capacities at other temperature differences, multiply by factor in Table 15.
Table 16
Refrigeration Gas
Heat Reclaim
1/2" and 5/8" tube, 50°F TD, entering air to condensing temperatire
Type A and Type 5, hot gas reclaim, heating capacities
MBH per SQ FT of coil face area
FPM, Type A Coils (1/2" DIA.)
FPM, Type 5 Coils (5/8" DIA.)
Rows FPI
400
450
500
550
600
400
450
500
550
600
6
7.70
8.18
9.43
9.90
10.25
9.25
9.85
10.41
10.91
11.41
8
8.90
9.45
10.90
11.38
11.85 10.04
10.70
11.33
11.92
12.47
2
10 10.40 11.05 12.15
12.73
13.18 11.12
11.93
12.68
13.37
14.03
12 11.70 12.45 13.13
13.77
14.35 12.20
13.13
13.99
14.80
15.56
14 12.88 13.73 14.48
15.18
15.83 13.23
14.28
15.26
16.18
17.04
6
11.08 11.96 12.88
13.50
13.98 12.27
13.13
13.98
14.77
15.52
8
12.60 13.60 14.56
15.25
15.90 13.17
14.13
15.07
15.96
16.79
3
10 13.93 14.95 15.93
16.80
17.63 14.30
15.48
16.58
17.61
18.58
12 14.91 16.02 17.08
18.03
18.95 15.40
16.73
17.98
19.16
20.28
14 16.08 17.30 18.50
19.55
20.58 16.39
17.87
19.28
20.60
21.86
6
13.27 14.35 15.53
16.38
17.18 14.50
15.66
16.77
17.81
18.79
8
14.98 16.21 17.43
18.47
19.47 15.39
16.66
17.89
19.04
20.12
4
10 16.20 17.48 18.75
19.92
21.07 16.50
17.96
19.36
20.68
21.94
12 17.47 18.73 19.98
21.25
22.50 17.48
19.11
20.68
22.17
23.58
14 18.57 19.95 21.30
22.65
23.97 18.32
20.11
21.83
23.48
25.05
6
16.41 17.83 19.58
20.78
21.90 17.38
19.10
20.62
22.09
23.49
8
18.35 19.93 21.50
23.10
24.67 18.10
19.96
21.61
23.21
24.74
6
10 19.13 20.90 22.63
24.20
25.75 18.96
21.00
22.83
24.62
26.33
12 19.80 21.70 23.58
25.23
26.87 19.65
21.83
23.82
25.78
27.67
14 19.87 22.01 24.02
26.02
27.95 20.18
22.48
24.61
26.72
28.75
6
18.25 20.08 21.75
23.45
25.08 18.93
21.51
23.02
24.69
26.42
8
19.29 21.31 23.16
25.04
26.86 19.49
21.82
23.82
25.60
27.47
8
10 20.04 22.23 24.24
26.30
28.28 20.11
22.57
24.74
26.67
28.71
12 20.51 22.82 24.95
27.14
29.26 20.58
23.12
25.43
27.63
29.68
14 20.82 23.22 25.44
27.72
29.95 20.91
23.51
25.93
28.25
30.45
Table 14
Coil Perfromance- Heat Reclaim MBH/SQ FT
Air Handler
Type A Large
Type 5 Large
Unit
Coil Face Area
Coil Face Area
Size
Square Feet
Square Feet
03
3.13
3.00
06
5.76
5.69
08
7.81
7.50
10
9.77
9.38
12
12.40
11.69
14
14.58
13.75
18
17.71
17.50
20
20.05
19.25
26
26.56
25.50
34
33.65
34.00
41
40.73
40.38
50
50.63
49.50
65
64.58
64.58
75
75.35
74.92
