AERCO BMK 3.0 LN Nat. Gas APRIL 2009 - Manual (Page 15)

INSTALLATION
2-5
2.7 GAS SUPPLY PIPING
The AERCO Benchmark 3.0 Gas Components
and Supply Design Guide, GF-3030 must be
consulted prior to designing or installing any gas
supply piping.
WARNING
NEVER USE MATCHES, CANDLES,
FLAMES OR OTHER SOURCES OF
IGNITION TO CHECK FOR GAS
LEAKS
.
CAUTION
Many soaps used for gas pipe leak
testing are corrosive to metals. There-
fore, piping must be rinsed thoroughly
with clean water after leak checks
have been completed.
All gas piping must be arranged so that it
does not interfere with removal of any
covers, inhibit service/maintenance, or
restrict access between the unit and
walls, or another unit.
A 2 inch gas inlet connection is located on the
rear of the unit as shown in Figure 2-4.
Prior to installation, all pipes should be de-
burred and internally cleared of any scale, metal
chips or other foreign particles. Do Not install
any flexible connectors or unapproved gas
fittings. Piping must be supported from the floor,
ceiling or walls only and must not be supported
by the unit.
A suitable piping compound, approved for use
with natural gas, should be used. Any excess
must be wiped off to prevent clogging of
components.
To avoid unit damage when pressure testing gas
piping, isolate the unit from the gas supply
piping. At no time should the gas pressure
applied to the unit exceed 2 psi. Leak test all
external piping thoroughly using a soap and
water solution or suitable equivalent. The gas
piping used must meet all applicable codes.
2.7.1 Gas Supply Specification
The gas supply input specifications to the unit
for Natural Gas are as follows:
The maximum static pressure to the unit must
not exceed 2 psi. The minimum operating gas
pressure for natural gas is 3.5” W.C. for FM and
4.0” W.C. for IRI gas trains when the unit is firing
at maximum input. The gas supply pressure to
the unit must be of sufficient capacity to provide
3000 cfh while maintaining the gas pressure at
3.5” W.C. for FM or 4.0” for IRI gas trains.
2.7.2 Manual Gas Shutoff Valve
A manual shut-off valve must be installed in the
gas supply line upstream of the Boiler as shown
in Figure 2-7. Maximum allowable gas pressure
to the Boiler is 2 psi
Figure 2-7
Manual Gas Shut-Off Valve Location