13
CONNECTING GAS SERVICE
Connect gas service from meter to control assembly in
1.
accordance with ANSI Z223.1 and local codes or utility.
A ground joint union should be installed for easy removal
of gas control for servicing. A drip leg or trap must be
installed at the bottom of a vertical section of piping at the
inlet to the boiler. A pipe compound resistant to the action
of liquified petroleum gases must be used on all threaded
pipe connections. Check with the local utility for location
of manual shutoff valve if required. See
figure #11
.
The gas line should be of adequate size to prevent undue
2.
pressure drop and never smaller than the pipe size of the
main gas control valve. See chart below.
Maximum Capacity of Pipe in Cubic Feet of
Gas Per Hour
(Gas pressure = 0.5 psig or less,
pre sure drop = .5 in.w/c)
Nomi
-
nal Iron
Pipe
Size
Length of Pipe (Feet)
10'
20'
30'
40'
60'
80'
100'
½"
175
120
97
82
66
57
50
¾"
360 250
200
170
138
118
103
1"
680 465
375
320
260
220
195
1¼"
1400 950
770
660
530
460
400
For additional information refer to the National Fuel
Gas Code Handbook, Latest Revision.
DO NOT USE AN OPEN FLAME.
WARNING
!
To check for leaks in gas piping, use a soap and water
3.
solution or other approved method.
Disconnect the boiler from the gas supply piping system
4.
during any pressure testing of the gas piping. After recon
-
necting, leak test the gas connection and boiler piping
before placing the boiler back into operation.
PRESSURE
GAS
NATURAL
PROPANE
MIN. SUPPLY
5" w.c.
11" w.c.
MAX. SUPPLY
14" w.c.
14" w.c.
MANIFOLD
3.5" w.c.
10.5" w.c.
Figure #11