Lochinvar Power-Fin, Руководство дизайнера

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LOCHINVAR CORPORATION
300 MADDOX SIMPSON PKWY
LEBANON, TN 37090
www.lochinvar.com
Designer’s Guide / Power-fin Water Heater
Chapter 3 – Gas Supply
Lochinvar products are designed with the concept of flame control. We develop combustion
systems that tightly control the flow of air and gas to deliver a clean and efficient burn. In
Chapters 1 and 2, we showed the various methods to deliver an ample quantity of air to the
appliance. In Chapter 3, we discuss delivering a steady and reliable supply of gas to the
appliance.
The key to the gas supply is sizing the gas line properly. The Power-fin will require less than a
half a pound of pressure. The following Sizing Chart is based on less than ½ pound of pressure
or less than 14 inches of pressure. The table is derived from the ANSI Z223.1, the National Fuel
Gas Code.
Simply calculate the total linear feet of straight gas pipe. Figure each elbow as equal to five
straight feet of pipe. Working down the column that matches your pipe length, find the value
GREATER THAN the total Btu/hr input of the water heater or water heaters. This will identify the
minimum nominal iron pipe size.
GAS PIPE SIZING CHART
Nominal
Iron Length of Pipe in Straight Feet
Pipe
Size 10 20 30 40 50 60 70 80 90 100 125 150 175 200
3/4" 369 256 205 174 155 141 128 121 113 106 95 86 79 74
1" 697 477 384 328 292 267 246 256 210 200 179 164 149 138
1 1/4" 1,400 974 789 677 595 543 502 472 441 410 369 333 308 287
1 1/2" 2,150 1,500 1,210 1,020 923 830 769 707 666 636 564 513 472 441
2" 4,100 2,820 2,260 1,950 1,720 1,560 1,440 1,330 1,250 1,180 1,100 974 871 820
2 1/2" 6,460 4,460 3,610 3,100 2,720 2,460 2,310 2,100 2,000 1,900 1,700 1,540 1,400 1,300
3" 11,200 7,900 6,400 5,400 4,870 4,410 4,000 3,800 3,540 3,300 3,000 2,720 2,500 2,340
4" 23,500 16,100 13,100 11,100 10,000 9,000 8,300 7,690 7,380 6,870 6,150 5,640 5,130 4,720
The Power-fin features a Negative-Regulation or Neg-Reg gas
combustion system. The gas is introduced upstream of the
combustion blower. As the blower draws air in, the negative
pressure on the inlet of the blower pulls the gas from the gas
valve. The gas/air mixture is pushed through the blower into the
burner. The gas/air mixture filters through the ceramic burner
mesh and is ignited by the Hot Surface Igniter.
On full fire, a crisp blue flame rises off the surface of the burner.
As demand decreases, the operating control reduces the blower
speed. The flame is reduced and touches the burner surface.
The ceramic burner material is designed to burn infra-red safely without being damaged by direct
contact of the flame. Even at this reduced Btu/hr input, the gas/air mixture is balanced to provide
clean, efficient combustion.
Gas