6 720 607 072
Appliance details
15
Fig. 20 Vertical venting installation - Masonry
Chimney (combustion air piping not being
shown)
A condensate drain tube must be attached to the
exhaust collar of the heater for all vent type applications,
see page, see page 11.
2.10 Gas piping & connections
Before c onnecting the gas supply, check the rating
plate on the right side of the heater to be sure that the
heater is rated for the same gas to which it will be
connected.
In the United States: The installation must conform with
local codes or, in the absence of local codes, the
National Fuel Gas Code ANSI Z223.1/NFPA 54.
In Canada: The Installation should conform with CGA
B149 INSTALLATION CODES and/or local installation
codes.
GAS LINE SIZING
The gas supply piping should be sized according to the
National Fuel Gas Code for a maximum draw of
175,000 BTUH. First determine the effective length of
the gas sup ply line by measuring the actual length of
piping, and then adding 5 ft. (1.52m) for every elbow or
“T” to the actual length. Use the charts in Fig. 22 to
determine the pipe diameter necessary to
accommodate the BTU (Wh) demand of the unit. If
there are more gas drawing appliances on the line, size
according to the maximum amount of BTU (Wh)
demand.
Note: It is important that if any flexible gas line is used,
above or below ground between the gas supply meter/
regulator and the water heater, that it be sized properly.
Consult the gas sizing specification tables provided by
the flexible gas line ma nufacturer and sample CSST
flexible gas line tables in Figure 22.
Fig. 21
BInstall a manual gas shut off valve, on the gas supply
line.
BThe use of a union when connecting gas pipe to the
gas inlet connection is critical, this will facilitate a ny
necessary s ervicing and cleaning of the inlet gas
particle screen.
BFlexible gas line connectors are not recommended
because they are commonly undersized and restrict
gas flow. Oversize the diameter of any flexible gas
appliance connector if one must be used.
Gas piping
Inlet gas particle screen