A · Second stage to appliances — Schedule 40 steel
11" WC inlet · 0.5" WC drop
Length (ft)1/2"3/4"1"1-1/4"1-1/2"2"
102916081,1502,3503,5206,790
202004187871,6202,4204,660
301603366321,3001,9403,750
401372875411,1101,6603,210
501222554809851,4802,840
601102314348921,3402,570
80941973727631,1402,200
100841753306771,0101,950
125741552926008991,730
150671402655438141,570
200581202274656971,340
250511072014126181,190
30046971823735601,080
B · First stage to second stage — PE pipe
10 PSIG inlet · 1 PSIG drop
Length (ft)1/2" CTS1" CTS3/4" IPS1" IPS1-1/4" IPS
101,3269,4037,63213,79423,890
209116,4625,2469,48116,419
307325,1904,2127,61313,185
406264,4423,6056,51611,285
505553,9373,1955,77510,002
605033,5672,8955,2339,062
804313,0532,4784,4797,756
1003822,7062,1963,9696,874
150 *3062,1731,7633,1875,520
200 *2621,8591,5092,7274,724
300 *2101,4931,2122,1903,793
400 *1801,2781,0371,8743,247
How to size a line
1. Add up the nameplate BTU of every appliance. 2. Measure the longest run, regulator to the farthest appliance. 3. Use the length row at or above that run. 4. Size the main on total load and each branch on its own load — every pipe off the same row. Pick the first size at or above the load.
Example
Furnace 100,000 + tankless 199,000 + range 65,000 = 364 MBH at 60 ft. Table A, 60 ft row: 1" carries 434 — main is 1". Tankless branch 199 → 3/4" (231). Second stage: MEGR-1222-BAF (500,000).