Part Number 550-142-302/0520
CGi
SERIES 4 — GAS-FIRED WATER BOILER —
Boiler Manual
30
Gas piping
5
Table 7
Pipe capacity for 0.60 specific gravity natural gas
Natural Gas:
1. Refer
to
Table 7
for pipe length and diameter. Base on rated
boiler input (divide by 1,000 to obtain cubic feet per hour).
Table 7
is only for gas with
specific gravity 0.60, with a
pressure drop through the gas piping of 0.30” w.c.
For
additional gas pipe sizing information, refer to ANSI Z223.1/
NFPA 54 – latest edition (or B149.1 or B149.2 for Canadian
Natural Gas and Propane Installation Code).
2. Inlet pressure required at gas valve inlet:
•
Maximum: 13” w.c.
•
Minimum: 5” w.c.
•
Manifold gas pressure: 3.5” w.c.
3. Install 100% lockup gas pressure regulator in supply line
if
inlet pressure exceeds 13” w.c.
Adjust for 13” w.c. maxi-
mum.
Propane Gas:
1. Contact gas supplier to size pipes, tanks and 100% lockup
gas pressure regulator.
2. Adjust propane supply regulator provided by gas supplier for
13” w.c. maximum pressure.
3. Inlet pressure required at gas valve inlet:
•
Maximum: 13” w.c.
•
Minimum: 11” w.c.
•
Manifold gas pressure: 10” w.c.
Connecting gas supply piping to
boiler
1. Remove jacket front panel and refer to
Figure 26
to pipe gas
to boiler.
a.
Install drip leg
at inlet of gas connection to boiler.
Where local utility requires drip leg to be extended to
the floor, use appropriate length of pipe between cap
and tee.
b.
Install ground joint union
for servicing, when re-
quired.
c.
Install manual shutoff valve
in gas supply piping out-
side boiler jacket when required by local codes or utility
requirements.
d.
In Canada
— When using manual main shutoff valve, it
must be identified
by the installer.
2.
Support piping
with hangers, not by boiler or its accessories.
3.
Purge all air
from gas supply piping.
4. Before placing boiler in operation,
check boiler and its gas
connection for leaks
.
a.
Close manual main shutoff valve
during any pressure
testing at less than 13” w.c.
b.
Disconnect boiler and gas valve from gas supply
piping
during any pressure testing greater than 13” w.c.
Do not check for gas leaks with an open
flame
— use bubble test. Failure to use bubble
test or check for gas leaks can cause severe
personal injury, death or substantial property
damage.
5.
Use pipe dope compatible with propane gases.
Apply
sparingly only to male threads of pipe joints so that pipe dope
does not block gas flow.
Failure to apply pipe dope
as detailed above
can result in severe personal injury, death or
substantial property damage.
Figure 26
Gas supply piping
Gas pipe
length
(feet)
Capacity of pipe for pipe size of:
(Capacity in cubic feet gas per hour)
½”
¾”
1”
1¼”
1½”
10
132
278
520
1050
1600
20
92
190
350
730
1100
30
73
152
285
590
860
40
63
130
245
500
760
50
56
115
215
440
670
75
45
93
175
360
545
100
38
79
150
305
460
150
31
64
120
250
380