Desa DynaVent DNV25NB, Owner'S Operation And Installation Manual

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OWNER’S MANUAL
Providing Gas Piping to Furnace
You must provide gas piping from gas source to furnace. The gas piping must be in a vertical
position where it connects to the furnace. This prevents interference with front cover
installation.
Consult your local gas company for proper routing of the gas lines.
Pipe size is determined by the length of pipe from the gas source to the furnace and the total
BTU load on the gas source.
Add the total BTUs required for all appliances connected to the gas source including this furnace.
Divide this number by 1030. This will give you the approximate cubic feet per hour needed.
Example:
40,000 BTU/Hr
+ 15,000 BTU/Hr for other gas appliances
55,000 BTU/Hr total
55,000
÷
1030 = 53.4
Locate 53.4 or higher on chart below.
According to the chart below, you should use 50 feet or less of 1/2" pipe, 200 feet
or less of 3/4" pipe, etc...
MINIMUM
IRON PIPE
SIZE LENGTH OF PIPE (FEET)
10 20 30 40 50 60 70 80 90 100 125 150 175 200
3/8" 72 49 40 34 30 27 25 23 22 21 18 17 15 14
1/2" 132 92 73 63 56 50 46 43 40 38 34 31 28 26
3/4" 278 190 152 130 115 105 96 90 84 79 72 64 59 55
1" 520 350 285 245 215 195 180 170 160 150 130 120 110 100
1
1
/
4
" 1050 730 590 500 440 400 370 350 320 305 275 250 225 210
1
1
/
2
" 1600 1100 890 760 670 610 560 530 490 460 410 380 350 320
2" 3050 2100 1650 1450 1270 1150 1050 990 930 870 780 710 650 610
2 1 /
2
" 4800 3300 2700 2300 2000 1850 1700 1600 1500 1400 1250 1130 1050 980
3" 8500 5900 4700 4100 3600 3250 3000 2800 2600 2500 2200 2000 1850 1700
4" 17500 12000 9700 8300 7400 6800 6200 5800 5400 5100 4500 4100 3800 3500
IMPORTANT:
Check gas line pressure at gas meter before connecting furnace to gas line. Gas
line pressure must be no less than 5 inches of water and no greater than 7 inches of water. Gas
pressures and input to the burners must not exceed the rated input and pressure shown on the
rating plate. For natural gas, manifold pressure should be 3.5 inches of water. For elevations
above 2000 feet, reduce rating 4% for each 1000 feet above sea level (U.S.A. only).
INSTALLATION
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