Install Instructions

40
SUPPLY GAS LINE INSTALLATION
Contact your local gas utility company to ensure that adequate
gas service is available and to review applicable installation
codes for your area.
Be sure that the gas meter has sufcient capacity to supply the
rated gas input of the water heater as well as the requirements
of all other gas red equipment supplied by the meter. If the
gas meter is undersized, the gas company will have to install a
properly sized gas meter.
Fire and Explosion Hazard
Turn off gas lines during installation.
Contact a qualified installer or service
agency for installation and service.
Excessive gas pressure to gas valve can
cause serious injury or death.
Do not use water heater with any gas
other than the gas shown on the rating
label.
Make sure gas supplied is same type listed on the water heater’s
rating label.
The water heaters covered in this manual are not intended for
operation at higher than 14.0" W. C. (2.62 kPa) for natural gas and
14.0" W. C. (3.49 kPa) for propane gas supply pressure, see Table
3 on page 11. The water heaters covered in this manual require
supply gas regulators to maintain required supply gas pressure.
Exposure to higher gas supply pressure may cause damage to the
gas controls which could result in re or explosion. If overpressure
has occurred such as through improper testing of gas lines or
malfunction of the supply system the water heater’s gas valve
must be checked for safe operation by a Qualied Service Agency.
Ensure supply regulator vent lines and the safety vent valves are
protected against blockage. These are components of the gas
supply system, not the water heater. Vent blockage may occur
during ice storms.
It is important to guard against gas valve fouling from
contaminants in the gas ways. Such fouling may cause improper
operation, re or explosion. If copper supply lines are used they
must be internally tinned and certied for gas service.
REGULATED GAS
SUPPLY LINE
MAIN GAS
SHUTOFF VALVE
TEE FITTING
PIPE CAP
SEDIMENT TRAP
Figure 54
Ensure all gas pipe is clean on the inside before installation. To
trap any dirt or foreign material in the gas supply line a sediment
trap must be installed as shown in Figure 54. The sediment trap
must be readily accessible and not subject to freezing conditions.
Install in accordance with the recommendations of the local gas
utility company.
GAS LINE SIZING
Depending on the developed equivalent length and/or the number
of appliances connected to a common main, the size of supply gas
lines may have to be increased.
Size the supply/main gas line(s) in accordance with Table 11
or Table 12. The values given in Table 11 and Table 12 are for
straight lengths of iron pipe at 0.5" W. C. (125 Pa) pressure drop,
which is considered normal for low pressure systems. Note that
ttings such as elbows and tees will add to the pipe pressure drop.
Schedule 40 Steel or Wrought Iron Pipe is the preferred material
for the gas line of this water heater. It is imperative to follow the
sizing recommendations in the latest version of the National Fuel
Gas Code if Corrugated Stainless Steel Tubing (CSST) is used
as the gas line for this water heater.
SUPPLY GAS LINE SIZING U. S. UNITS
TABLE 11
LENGTH
IN
FEET
NORMAL IRON PIPE SIZES (INCHES)
INPUT IN THOUSANDS BTU/HR
1/2” 3/4” 1” 1 1/4” 1 1/2” 2”
10 175 360 680 1400 2100 3960
20 120 250 485 950 1460 2750
30 97 200 375 770 1180 2200
40 82 170 320 660 990 1900
50 73 151 285 580 900 1680
60 66 138 260 530 810 1520
70 61 125 240 490 750 1400
80 57 118 220 460 690 1300
90 53 110 205 430 650 1220
100 50 103 195 400 620 1150
125 44 93 175 360 550 1020
150 40 84 160 325 500 950
175 37 77 145 300 460 850
200 35 72 135 280 430 800
SUPPLY GAS LINE SIZING METRIC UNITS
TABLE 12
LENGTH
IN
METERS
NORMAL IRON PIPE SIZES (INCHES)
INPUT IN kW
1/2” 3/4” 1” 1 1/4” 1 1/2” 2”
3.0 51 105 199 410 615 1160
6.1 35 73 142 278 428 805
9.1 28 59 110 225 346 644
12.2 24 50 94 193 290 556
15.2 21 44 83 170 264 492
18.3 19 40 76 155 237 445
21.3 18 37 70 143 220 410
24.4 17 35 64 135 202 381
27.4 16 32 60 126 190 357
30.5 15 30 57 117 182 337
38.1 13 27 51 105 161 299
45.7 12 25 47 95 146 278
53.3 11 23 42 88 135 249
61.0 10 21 40 82 126 234