Weil-McLain CGi Series 3 Installation And Maintenance Manual page 30

CG i
GAS-FIRED wATER BOILER- sERIEs a -
Boiler Manual
5
Gas piping
Connecting gas supply piping
to
boiler
I. 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 re<Juires drip leg to be extended to
the floor, use appropnate length of pipe between cap
and tee.
b. Install ground joint union for servicing, when re-
q uired.
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.
'" 1&-,-, W .,.,., AR ,.,. N "" IN~GI
Do not check for gas leaks with an open
flame
- use
bubble test Failure to use bubble
test or check fo r gas leaks can cause severe
personal injury, death or substantial property
dan1age.
5. Use pipe dope compatible with propane gases. Apply
sparingly only to male threads of pipe joints
so
that pipe dope
does no t block gas flow.
I& WARNING!
Failure to apply pipe dope as detailed above
can result in severe personal injury, death or
Natural Gas:
I. 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 o nly 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 infom1ation, refer to ANSI Z223. 1
(or BI49.I or BI49.2 fo r Canadian installations).
2. Inlet pressure required at gas valve inlet:
tvtaximum:
13"
w.c.
tvtinirnum:
5"
w.c.
JV!anifold gas pressure: 3.5" w.c.
3.
Install 100% lockup gas pressure regulator in su pply line if
inlet pressure exceeds 13" w.c. Adjust for I 3" w.c. maxi-
mum.
Propane Gas:
I.
Contact gas supplier to size pipes, tanks and I
00%
lockup
gas pressure regulator.
2. Adjust propane supply
regulator provided by gas supplier for
13"
w.c. maximmn pressure.
3. Inlet pressure required at gas valve inlet:
Maximum: 1 3" w.c.
tvtinirnum:
11 ,
w.c.
Manifold gas pressure: 10" w.c.
substantial property dam age. Figure 26 Gas supply piping
Table 7 Pipe capacity for 0.60 specific grav~y natural gas
Gas pipe
Capacity of pipe for pipe size of:
length
(Capacity in cubic feet gas per hour)
(feet)
1/a"
~·
1"
1f/•"
11/a"
10 132 278
520
1050 1800
20
92
190
350
730 1100
30 73 152
285
590
880
40
83
130 245 500 760
50
58
115 215 440
670
75
45
93 175 360
545
100
38
79 150 305 460
150 31
64
120 250
360
71028
30
Part Number 550-142-780/0712