Reznor EEDU Unit Installation Manual - Manual (Page 9)

Form I-EEDU, P/N 150492 R6, Page 9
6.0 Mechanical
This appliance is equipped for a maximum gas supply pressure of
1/2 psi, 3.4 kPa, or 14 inches water column. NOTE: Supply pressure
higher than 1/2 psi 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.
6.1 Gas Piping and
Pressures
6.1.1 Gas Supply and Connections
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
of Pipe
Diameter of Pipe
1/2" 3/4" 1" 1-1/4" 1-1/2" 2"
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.
Sizing Gas Supply
Lines
All piping must be in accordance with requirements outlined in the National Fuel Gas
Code ANSI/Z223.1 (latest edition) or CSA-B149.1 and B149.2 (See Paragraph 1.4).
Gas supply piping installation should conform with good practice and with local codes.
Duct furnaces for natural gas are orificed for operation with gas having a heating value
of 1000 (± 50) BTU per cubic ft. If the gas at the installation does not meet this specifi-
cation, consult the factory for proper orificing.
Pipe joint compounds (pipe dope) shall be resistant to the action of liquefied
petroleum gas or any other chemical constituents of the gas being supplied.
Install a ground joint union and manual shutoff valve upstream of the unit control sys-
tem, as shown in FIGURE 8. The 1/8" plugged tapping in the shutoff valve provides
connection for supply line pressure test gauge. The National Fuel Gas Code requires
the installation of a trap with a minimum 3" drip leg. Local codes may require a mini-
mum drip leg longer than 3" (typically 6").
From Gas Supply
(horizontal or vertical)
Manual shutoff
Drip
Leg
To Gas Valve
To Gas Valve
Ground
Joint
Union
Drip
Leg
Ground Joint Union
Manual shutoff
FIGURE 8 - Supply Piping Connection
Gas Connection to
Single-Stage Valve
(Not Gas Supply Line Size)
Unit Size 75-250 300-400
Natural Gas 1/2" 3/4"
Propane 1/2" 1/2"
NOTE: To permit burner removal, this nipple
must extend beyond the edge of the heater.