Connections; Boiler Connections; Gas Pipe Connection; Gas Line Connection - Slant/Fin VGH-299-CH Installation And Service Manual

7

CONNECTIONS

1 2

Gas pipe connection

The gas supply piping must conform to all local codes and regulations and/or National Fuel Gas Code, ANSI
Z223.1/NFPA 54. In Canada refer to CAN/CGA B149.1 installation codes, and local codes for gas piping
requirements and sizing. Pipe size running to the appliance depends on: Length of pipe; Number of fittings;
Maximum input requirement of all gas appliances in the residence. See the gas sizing table below for help when
sizing the gas connection. For information on propane sizing consult your local propane gas supplier.
Schedule 40
(Based on inlet pressure less than 2 psi, pressure drop of 0.3 W.C. and specific gravity 0.6)
Nominal Pipe
Size (In)
Length (ft)
10
20
30
40
50
60
70
80
90
100
Table 7. 1
7.2.1 G
AS LINE CONNECTION
Consult, the gas code to determine gas pipe size. It is required to install a manual shutoff gas valve in front of the
gas pressure regulator to make sure that the gas line can be closed in case of maintenance. The entire piping
system, gas meter and regulator must be sized properly to prevent pressure drop greater than 1 "wc as stated in
the NFPA54. If you experience a pressure drop of greater than 1" w.c., regulator or gas line is undersized.
Slant/Fin recommends a nominal value of 7" to 10" W.C. of gas pressure when using Natural gas and 11 to 13"
W.C. when using LPG, will be available at the boiler gas valve inlet at maximum boiler firing rate. See technical
specifications datasheet for minimum and maximum allowed gas pressures.
When an in-line regulator is used to drop gas pressure from 2 psi to 0.5 psi, it must be located a minimum of 6 ft
from the boiler.
Slant Fin requires a minimum 1" diameter flex hose if flex gas hose is going to be used. Ensure that: the gas line
connection to the appliance does not apply any weight or pressure to the gas valve.
Create an installation layout such that the piping does not interfere with the vent pipe, or any other serviceable
components.
The appliance shall be installed such that the gas ignition system components are protected from water (dripping,
spraying, rain etc.) during installation, operation and servicing.
No appreciable drop in line pressure may occur when any unit (or in the instance of a cascade installation when
all of the installed units).
lights or runs. Use common gas line sizing practices. Make sure the gas pressure is within specification during all
conditions. Always use a pipe-threading compound. Apply sparingly to all male threads, starting at two threads
from the end. Over doping or applying dope to the female end, can result in a blocked gas line.
DO NOT TIGHTEN FITTINGS WITHOUT SUPPORTING THE GAS VALVE, A BACKING WRENCH MUST BE
USED
20
1 – Water outlet / Flow
2 – Water inlet / Return
3 – Gas
4 – Condensate trap clean out.
5 – Condensate drain
6 – Automatic air drain.
Figure 7. 1
3 4 5 6
Black Steel Pipe in Cubic Feet of Natural Gas per Hour.
¾" 1"
273 514
188 353
151 284
129 243
114 215
104 195
95 179
89 167
83 157
79 148
E93.1601EN032.C VGH installation manual

Boiler connections

1¼" 1½"
1060 1580
726 1090
583 873
499 747
442 662
400 600
368 552
343 514
322 482
304 455
2"
3050
2090
1680
1440
1280
1160
1090
989
928
877