Table of Contents
Advertisement
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 sufficient capacity to supply the
rated gas input of the water heater as well as the requirements
of all other gas fired 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
Do not use water heater with any gas
other than the gas shown on the rating
label.
Excessive gas pressure to gas valve can
cause serious injury or death.
Turn off gas lines during installation.
Contact a qualified installer or service
agency for installation and service.
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 10.5" W. C. (2.62 kPa) for natural gas
and 14.0" W. C. (3.49 kPa) for propane gas supply pressure,
see Table 4 on page 13. 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 fire 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 Qualified
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, fire or explosion. If copper supply lines are used they
must be internally tinned and certified for gas service.
REGULATED GAS
SUPPLY LINE
MAIN GAS
SHUTOFF VALVE
TEE FITTING
SEDIMENT TRAP
(DRIP LEG)
PIPE CAP
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 (drip leg) must be installed as shown in Figure
48. 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.
figure 48
gAs LInE sIZIng
dO nOt use flexible gas piping.
minimum required supply gas line sizes are shown in the Supply
Gas regulator on page 13. 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 8 or
Table 9. The values given in Table 8 and Table 9 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 fittings
such as elbows and tees will add to the pipe pressure drop.
suPPLy gAs LInE sIZIng u. s. unIts
tAbLE 8
leNGTH
NormAl IroN PIPe SIZeS (INCHeS)
IN
INPuT IN THouSANDS bTu/Hr
Feet
1/2"
3/4"
10
175
360
20
120
250
30
97
200
40
82
170
50
73
151
60
66
138
70
61
125
80
57
118
90
53
110
100
50
103
125
44
93
150
40
84
175
37
77
200
35
72
suPPLy gAs LInE sIZIng MEtRIC unIts
tAbLE 9
leNGTH
NormAl IroN PIPe SIZeS (INCHeS)
IN
MeterS
1/2"
3/4"
3.0
51
105
6.1
35
73
9.1
28
59
12.2
24
50
15.2
21
44
18.3
19
40
21.3
18
37
24.4
17
35
27.4
16
32
30.5
15
30
38.1
13
27
45.7
12
25
53.3
11
23
61.0
10
21
37
1"
1 1/4"
1 1/2"
680
1400
2100
3960
485
950
1460
2750
375
770
1180
2200
320
660
990
1900
285
580
900
1680
260
530
810
1520
240
490
750
1400
220
460
690
1300
205
430
650
1220
195
400
620
1150
175
360
550
1020
160
325
500
145
300
460
135
280
430
INPuT IN kW
1"
1 1/4"
1 1/2"
199
410
615
1160
142
278
428
110
225
346
94
193
290
83
170
264
76
155
237
70
143
220
64
135
202
60
126
190
57
117
182
51
105
161
47
95
146
42
88
135
40
82
126
2"
950
850
800
2"
805
644
556
492
445
410
381
357
337
299
278
249
234
Advertisement
Table of Contents
