User Guide

21
Table 5. The sizes shown are for straight lengths of pipe
at 0.5 in. W.C. pressure drop, which is considered normal
for low pressure systems. Note: Fittings such as elbows,
tees and line regulators will add to the pipe pressure
drop. Also refer to the current editions of the National
Fuel Gas Code (NFPA 54) or Natural Gas and Propane
Installation Code (CAN/CSA B149.1).
Make sure gas supplied is same type listed on model
rating plate. The inlet gas pressure must not exceed 14
inch water column (2.6 kPa) for natural and propane
(L.P.) gas. The minimum inlet gas pressure shown on
rating plate is that which will permit ring at rated input.
If the gas control valve is subjected to pressures
exceeding 1/2 pound per square inch (3.5 kPa), the
damage to the gas control valve could result in a re or
explosion from leaking gas.
If the main gas line shut-off serving all gas appliances is
used, also turn “off” the gas at each appliance. Leave all
gas appliances shut “off” until the water heater installation
is complete.
A gas line of sufcient size must be run to the water
heater. Consult the current edition of National Fuel Gas
Code ANSI Z223.1/NFPA 54 or the Natural Gas and Propane
Installation Code CAN/CSA B149.1 and your gas supplier
concerning pipe size.
The gas piping must include the following:
• A readily accessible manual shut off valve in the gas
supply line serving the water heater, and
• A sediment trap ahead of the gas control valve to help
prevent dirt and foreign materials from entering the
gas control valve.
• A exible gas connector or a ground joint union
between the shut off valve and control valve to permit
servicing of the unit.
Be sure to check all the gas piping for leaks before
lighting the water heater. Use a soapy water solution, not
a match or open ame. Rinse off soapy solution and wipe
dry.
The minimum inlet gas pressure shown on the rating
plate is that which will permit ring at the rated input.
GAS SUPPLY LINE SIZES (IN INCHES)* MAXIMUM CAPACITY
OF PIPE IN CUBIC FEET PER HOUR
TABLE 4. INPUT IN THOUSANDS (BTU/HR)
LENGTH
IN
FEET
NOMINAL IRON PIPE SIZES ( INCHES )
1/2" 3/4" 1" 1 1/4" 1 1/2" 2" 2 1/2" 3" 4"
10 175 360 680 1400 2100 3960 6300 11000 23000
20 120 250 465 950 1460 2750 4360 7700 15800
30 97 200 375 770 1180 2200 3520 6250 12800
40 82 170 320 660 990 1900 3000 5300 10900
50 73 151 285 580 900 1680 2650 4750 9700
60 66 138 260 530 810 1520 2400 4300 8800
70 61 125 240 490 750 1400 2250 3900 8100
80 57 118 220 460 690 1300 2050 3700 7500
90 53 110 205 430 650 1220 1950 3450 7200
100 50 103 195 400 620 1150 1850 3250 6700
125 44 93 175 360 550 1020 1650 2950 6000
150 40 84 160 325 500 950 1500 2650 5500
175 37 77 145 300 460 850 1370 2450 5000
200 35 72 135 280 430
800
1280 2280
4600
TABLE 5. INPUT IN KW
LENGTH
IN
METERS
NOMINAL IRON PIPE SIZES ( INCHES )
1/2" 3/4" 1" 1 1/4" 1 1/2" 2" 2 1/2" 3" 4"
3 51 105 199 410 615 1160 1845 3221 6735
6 35 73 142 278 428 805 1277 2255 4626
9 28 59 110 225 346 644 1031 1830 3748
12 24 50 94 193 290 556 878 1552 3192
15 21 44 83 170 264 492 776 1391 2840
18 19 40 76 155 237 445 703 1259 2577
21 18 37 70 143 220 410 659 1142 2372
24 17 35 64 135 202 381 600 1083 2196
27 16 32 60 126 190 357 571 1010 2108
31 15 30 57 117 182 337 542 952 1962
38 13 27 51 105 161 299 483 864 1757
46 12 25 47 95 146 278 439 776 1610
53 11 23 42 88 135 249 401 717 1464
61 10 21 40 82 126 234 375 688 1347
Use pipe joint compound or teon tape marked as being
resistant to the action of petroleum [Propane (L.P.)]
gases.
The water heater and its gas connection must be leak
tested before placing the water heater in operation.