Install Instructions

18
V. Gas Piping
A. Size gas piping. Design system to provide adequate gas
supply to boiler. Consider these factors:
1. Allowable pressure drop from point of delivery to
boiler. Maximum allowable system pressure is ½
psig. Actual point of delivery pressure may be less;
contact gas supplier for additional information.
Minimum gas valve inlet pressure is listed on rating
label on front of boiler.
2. Maximum gas demand. Table 3 lists boiler input
rate. Also consider existing and expected future gas
utilization equipment (i.e. water heater, cooking
equipment).
Table 3: Rated Input
3. Length of piping and number of fittings. Refer to
Table 4 for maximum capacity of Schedule 40 pipe.
Table 5 lists equivalent pipe length for standard
fittings.
4. Specific gravity of gas. Corrections for the specific
gravity of natural gas can be found in Table 6.
For materials or conditions other than those listed
above, refer to National Fuel Gas Code, NFPA
54/ANSI Z223.1, or size system using standard
engineering methods acceptable to authority having
jurisdiction.
B. Connect boiler gas valve to gas supply system.
WARNING
Failure to use proper thread compounds on all
gas connectors may result in leaks of ammable
gas.
WARNING
Gas supply to boiler and system must be
absolutely shut off prior to installing or servicing
boiler gas piping.
1. Use methods and materials in accordance with local
plumbing codes and requirements of gas supplier. In
absence of such requirements, follow National Fuel
Gas Code, NFPA 54/ANSI Z223.1.
2. Use thread (joint) compounds (pipe dope) resistant
to action of liquefied petroleum gas.
3. Install sediment trap, ground-joint union and manual
shut-off valve upstream of boiler gas control valve.
See Figure 10.
Figure 10: Recommended Gas Piping
4. All above ground gas piping upstream from manual
shut-off valve must be electrically continuous and
bonded to a grounding electrode. Do not use gas
piping as grounding electrode. Refer to National
Electrical Code, ANSI/NFPA 70.
WARNING
Failure to properly pipe gas supply to boiler may
result in improper operation and damage to the
boiler or structure. Always assure gas piping is
absolutely leak free and of the proper size and
type for the connected load.
An additional gas pressure regulator may be
needed. Consult gas supplier.
Boiler
Model
Number
Input Rate
[cubic feet per hour]
Gas
Connection
Size
Natural
Gas
LP/Propane
PVCG30 62 24¾ ½
PVCG40 96 38½ ½
PVCG50 130 52 ½
PVCG60 164 65¾ ½