Detroit Radiant Products Company UH Series - Manual (Page 19)

19
UH Series
Chart 3.4 • Maximum capacity for Schedule 40 Metallic pipe, in CFH
The UH Series heater is equipped to receive a gas supply line nipple of ½”NPT Schedule 40 metallic
pipe. All piping must be installed in accordance with the requirements outlined in the National Fuel Gas
Code ANSI/Z223.1 (latest edition) or CSA-B149.1 and B149.2. Support all gas supply piping with pipe
hangers, metal strapping, or other suitable material. Do not rely on the heater to support the gas pipe.
When connecting piping to the unit, the use of a thread joint compound is required. The thread
compound (pipe dope) shall be resistant to the action of liquefied petroleum gas or any other chemical
constituents of the gas to be conducted through the piping. Use of Teflon
® tape is not permitted.
Install a ground joint union with a brass seat and a manual shut off valve adjacent the unit for
emergency shut off and easy servicing of controls. A 1/8” NPT plugged tap that is accessible for a test
gauge connections is also recommended, as illustrated in Figure 3.4.
A sediment trap must be installed in the supply line in the lowest spot prior to connecting to the heater.
The trap length shall be at least three inches long. Ideally, the trap would be installed as close as
possible to the shut off, as shown in Figure 3.4.
3.0 Installation • Gas Supply Installation Instructions
Pipe
Length
(feet)
1/2” 3/4” 1” 1-1/4” 1-1/2” 2”
Nat L.P. Nat L.P. Nat L.P. Nat L.P. Nat L.P. Nat L.P.
10’ 132 86 278 182 520 340 1050 686 1600 1046 3050 1993
20’ 92 60 190 124 350 229 730 477 1100 719 2100 1373
30’ 73 48 152 99 285 186 590 386 890 582 1650 1078
40’ 63 41 130 85 245 160 500 327 760 497 1450 948
50’ 56 37 115 75 215 141 440 288 670 438 1270 830
60’ 50 33 105 69 195 127 400 261 610 399 1150 752
70’ 46 30 96 63 180 118 370 242 560 366 1050 686
80’ 43 28 90 59 170 111 350 229 530 346 990 647
90’ 40 26 84 55 160 105 320 209 490 320 930 608
100’ 38 25 79 52 150 98 305 199 460 301 870 569
125’ 34 22 72 47 130 85 275 180 410 268 780 510
150’ 31 20 64 42 120 78 250 163 380 248 710 464
175’ 28 18 59 39 110 72 225 147 350 229 650 425
200’ 26 17 55 36 100 65 210 137 320 209 610 399
WARNING
!
Always use two (2) opposing wrenches to tighten mating pipe connections
to prevent excessive torque on the gas valve and manifold pipe. Excessive
torque can damage the valve and/or misalign the orifice, resulting in fire,
explosion, serious injury or death.