Lochinvar GAS HEATER FOR COMMERICAL POOL Installation And Service Manual page 29

Installation and Service Manual
13. Remove the manometer and related fitting from the "inlet"
side of the gas valve, replace 1/8" hex plug in the gas valve
and tighten.
14. Turn on the gas supply at the manual valve, turn on L.P.
gas at the tank if required.
15. Turn the power switch to the "ON" position.
16. Turn the gas valve knobs to the "ON" position.
17. Set the temperature control to call for heat.
WARNING: After completing any testing on
the gas system, leak test all gas connections.
Apply a soap/water
connections while main burners are operating.
Bubbles forming indicate a leak. Repair all leaks
at once. Do not operate this pool heater with a
leak in the gas train, valves or related piping.
Check burner performance by cycling the system while you
observe burner response. Burners should ignite promptly.
Flame pattern should be stable, see Burner Flames, page 47.
Turn system off and allow burners to cool, then cycle burners
again to ensure proper ignition and flame characteristics.
Nominal Iron
Pipe Size,
(Inches) 10
"
3/4 369
1" 697
"
1 1/4 1,400
"
1 1/2 2,150
2" 4,100
2-1/2" 6,460
3" 11,200
4" 23,500 16,100
Maximum capacity of pipe in thousands of BTU's per hour for gas pressures of 14 Inches Water Column (0.5 PSIG) or less and a total system
pressure drop of 0.5 Inch Water Column (Based on NAT GAS, 1025 BTU's per Cubic Foot of Gas and 0.60 Specific Gravity).
solution to all
Multiple Unit Installations Gas Supply Pipe Sizing
20 30 40
256 205 174
477 384 328
974 789 677
1,500 1,210 1,020
2,820 2,260 1,950 1,720
4,460 3,610 3,100 2,720
7,900 6,400 5,400 4,870
13,100 11,100 10,000
gas
Figure 30 – Measuring Gas Supply Pressure at
Combination Gas Valve
TABLE - K
Length of Pipe In Straight Feet
50 60 70 80
155 141 128 121
292 267 246 256
595 543 502 472
923 830 769 707
1,560 1,440 1,330
2,460 2,310 2,100 2,000 1,900
4,410 4,000 3,800 3,540 3,300
9,000 8,300 7,690 7,380 6,870
29
90 100 125 150
113 106 95 86
210 200 179 164
441 410 369 333
666 636 564 513
1,250 1,180 1,100 974
1,700 1,540 1,400 1,300
3,000 2,720 2,500 2,340
6,150 5,640 5,130 4,720
175 200
79 74
149 138
308 287
472 441
871 820