Table 4 - Maximum Capacity* for Copper Tube in a Low Pressure System of Less than 14 inches wc and Pressure Drop of 1 inch wc, CFH.**

Length of Tube, feetOutside Diameter of Tube, inches
3/81/25/83/47/81 1/81 3/8
10 35 72 147 257 364 778 1401
20 24 50 101 176 250 535 963
30 19 40 81 142 201 429 773
40 17 34 69 121 172 368 662
50 15 30 61 107 152 326 586
60 13 27 56 97 138 295 531
70 12 25 51 90 127 272 489
80 11 23 48 83 118 253 455
90 11 22 45 78 111 237 427
100 10 21 42 74 105 224 403
125 8.9 18 37 65 93 198 357
150 8.1 17 34 59 84 180 324
175 7.4 15 31 55 77 165 298
200 6.9 14 29 51 72 154 277
250 6.1 13 26 45 64 136 245
Notes:
* Includes 20% factor for fittings.
** See Table 7.