Watts AERCO Benchmark 2.0, Руководство пользователя

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INSTALLATION
2-4
CAUTION!
Many soaps used for gas pipe leak testing
are corrosive to metals. The piping must be
rinsed thoroughly with clean water after leak
checks have been completed .
NOTE:
All gas piping must be arranged so that it
does not interfere with removal of any
cover, inhibit service or maintenance, or
prevent access between the Unit and walls,
or another unit.
The location of the 2" inlet gas connection is
located on the rear of the unit as shown in
Figure 2.5.
All pipes should be de-burred and internally
cleared of any scale or iron chips before
installation. No flexible connectors or non-
approved gas fittings should be installed. Piping
should be supported from floor, ceiling or walls
only and must not be secured to the unit.
A suitable piping compound, approved for use
with natural gas or propane, should be used.
Any excess must be wiped off to prevent
clogging of components.
To avoid damage to the unit, when pressure
testing gas piping, isolate the unit from the gas
supply piping. At no time should there be more
than 14” W.C. to the unit. Leak test all external
piping thoroughly for leaks using a soap and
water solution or suitable equivalent. The gas
piping must meet all applicable codes.
2.4.1 GAS SUPPLY SPECIFICATONS
AND GAS SUPPLY REGULATORS
− Natural Gas:
The maximum static pressure to the unit
must be no more than 14” W.C. Minimum
operating gas pressure for natural gas is
7.0” W.C. for FM gas trains & 7.4” W.C. for
IRI gas trains when the unit is firing at
maximum input. Proper sizing of the gas
supply regulator in delivering the correct gas
flow and outlet pressure is mandatory. The
gas supply pressure regulator must be of
sufficient capacity volume to provide 2000
cfh while maintaining the gas pressure at
7.0” W.C. for FM gas trains & 7.4” W.C. for
IRI gas trains and should have no more than
1" droop from minimum to full fire.
− Propane for Dual Fuel Unit:
The maximum static pressure to the unit
must be no more than 14” W.C. Minimum
operating gas pressure for propane is 7.0”
W.C. for FM gas trains and 7.4” W.C. for IRI
gas trains when the unit is firing at maximum
input. Proper sizing of the gas supply
regulator in delivering the correct gas flow
and outlet pressure is mandatory. The gas
supply pressure regulator must be of
sufficient capacity volume to provide 800 cfh
while maintaining the gas pressure at 7.0”
W.C. for FM gas trains and 7.4” W.C. for IRI
gas trains, and should have no more than 1"
droop from minimum to full fire.
A Maxitrol RV-91 gas supply regulator is
supplied by AERCO and must be positioned as
shown in figure 2.5. For a dual fuel unit, two RV-
91 regulators are supplied. Maximum gas
pressure to the RV-91 is 14" W.C. If the gas
supply pressure will exceed 14" W.C., a lock -up
style regulator is required up stream of the RV-
91.
When installing the gas supply regulator(s),
union connections should be placed in the
proper locations to allow for maintenance.
The gas supply regulator must be properly
vented to outdoors. Consult the local gas utility
for exact requirements concerning venting of
supply gas regulators.
NOTE:
If a regulator other than the Maxitrol RV-91
supplied with the boiler is used it must be
capable or regulating 2,000,000 BTU/HR of
natural gas while maintaining 7” W.C. to the
boiler.
CAUTION!
A lockup style regulator must be used when
gas supply pressure exceeds 14” W.C.
2.4.2 MANUAL GAS SHUTOFF VALVE
A 2” manual gas shut-off valve is furnished with
each unit. The valve should be positioned as
shown in Figure 2.5 upstream of the supply
regulator in a readily accessible location.
2.4.3 IRI GAS TRAIN KIT
The IRI gas train is an optional gas train
required in some areas by code or for insurance
purposes. The IRI gas train is factory pre-piped
and wired. See Appendix F, Drawing Number
AP-A-742, or AP-A-745 (Dual-Fuel).