Reznor VR Unit Installation Manual - Manual (Page 22)

Form I-VR, P/N 205202 R13, Page 21
WARNING: This appliance is equipped for a maximum gas supply pressure of 1/2
pound, 8 ounces, or 14 inches water column.
NOTE: Supply pressure higher than 1/2 pound requires installation of an additional service regulator external
to the unit.
PRESSURE TESTING SUPPLY PIPING
Test Pressures Above 1/2 PSI: Disconnect the heater and manual valve from the gas supply line which is
to be tested. Cap or plug the supply line.
Test Pressures Below 1/2 PSI: Before testing, close the manual valve on the heater.
Sizing
Gas
Supply
Lines
Capacity of Piping
Cubic Feet per Hour based on 0.3” w.c. Pressure Drop
Specific Gravity for Natural Gas -- 0.6 (Natural Gas -- 1000 BTU/Cubic Ft)
Specific Gravity for Propane Gas -- 1.6 (Propane Gas -- 2550 BTU/Cubic Ft)
Length Diameter of Pipe
of 1/2” 3/4” 1” 1-1/4” 1-1/2” 2”
Pipe Natural Propane Natural Propane Natural Propane Natural Propane Natural Propane Natural Propane
20’ 92 56 190 116 350 214 730 445 1100 671 2100 1281
30’ 73 45 152 93 285 174 590 360 890 543 1650 1007
40’ 63 38 130 79 245 149 500 305 760 464 1450 885
50’ 56 34 115 70 215 131 440 268 670 409 1270 775
60’ 50 31 105 64 195 119 400 244 610 372 1105 674
70’ 46 28 96 59 180 110 370 226 560 342 1050 641
80’ 43 26 90 55 170 104 350 214 530 323 990 604
90’ 40 24 84 51 160 98 320 195 490 299 930 567
100’ 38 23 79 48 150 92 305 186 460 281 870 531
125’ 34 21 72 44 130 79 275 168 410 250 780 476
150’ 31 19 64 39 120 73 250 153 380 232 710 433
175’ 28 17 59 36 110 67 225 137 350 214 650 397
200’ 26 16 55 34 100 61 210 128 320 195 610 372
Note: When sizing supply lines, consider possibilities of future expansion and increased requirements.
Refer to National Fuel Gas Code for additional information on line sizing.
DANGER: Do not install gas piping where it may be exposed to radiant or convection
heat. See Hazard Levels, page 2.
Since the tubular heater does expand and contract, the connection between the
supply line and the heater must allow for expansion and contraction. Use only
an agency certified, stainless steel connector with a length of 36” (9140mm)
and a minimum size of 3/4” I.D.
Canadian Installation NOTE: The Natural Gas and Propane Installation Code,
CAN/CSA B149.1, requires a Type I hose connector certified to CAN/CGA-8.1
with a length of 36 (±6) inches / 90 (±15) cm. Type I hose is field supplied when
required.
In the United States, if a 36” stainless flexible connector, Option CE4, was
ordered with the heater, it will be shipped separately. Pressure drops for Option
CE4 stainless flexible connector are listed in the table below.
A shutoff valve and a drip leg or sediment trap must be provided in the gas sup-
ply line at each heater. See FIGURE 23, page 22.
Pressure Drop (Inches W.C.)
BTUH Input Option CE4, 3/4” I.D.
50,000 0.05
75,000 0.05
100,000 0.10
125,000 0.15
150,000 0.20
175,000 0.40
200,000 0.50
WARNING: Strong
cleaning solutions
or chemical
substances must
not come in
contact with the
flexible connector.
Gas Connection
Requirements