AERCO BMK 3.0 LN Nat. Gas APRIL 2009 - Manual (Page 34)

INITIAL START-UP
4. Install a NPT-to-barbed fitting into the
tapped plug port.
5. Attach one end of the plastic tubing to the
barbed fitting and the other end to the 16
inch W.C. manometer.
TO
AIR/FUEL
VALVE
GAS
INLET
SSOV
1/8" NPT PLUG
(INSTALL MANOMETER HERE)
HIGH GAS
PRESSURE
SWITCH
LEAK DETECTION
BALL VALVE
LOW GAS
PRESSURE
SWITCH
Figure 4-1.
1/8 Inch Gas Plug Location
4.2.3 Accessing the Vent Probe Port
The unit contains NPT plugs on both the left and
right side of the exhaust manifold at the rear of
the unit as shown in Figure 4-2.
Figure 4-2
Analyzer Probe Hole Location
Prepare the port for the combustion analyzer
probe as follows:
1. Remove the plug from the probe port on the
left or right side of the exhaust manifold.
2. If necessary, adjust the stop on the
combustion analyzer probe so that it will
extend mid-way into the flue gas flow. DO
NOT install the probe at this time.
IMPORTANT
The Combustion Calibration proce-
dure specified in paragraph 4.3
applies ONLY to units with serial
numbers G-07-1901 and above.
For units with serial numbers below
G-07-1901, use the Combustion
Calibration procedure provided in
Appendix K.
4.3 NATURAL GAS COMBUSTION
CALIBRATION
The Benchmark 3.0LN Boiler is combustion
calibrated at the factory prior to shipping.
However, recalibration as part of initial start-up
is necessary due to changes in the local altitude,
gas BTU content, gas supply piping and supply
regulators. Factory Test Data sheets are
shipped with each unit. These sheets must be
filled out and returned to AERCO for proper
Warranty Validation.
It is important to perform the following procedure
as outlined. This will keep readjustments to a
minimum and provide optimum performance.
1. Open the water supply and return valves to
the unit and ensure that the system pumps
are running.
2. Open the natural gas supply valve(s) to the
unit.
3. Set the control panel ON/OFF switch to the
OFF position.
4. Turn on external AC power to the unit. The
display will show LOSS OF POWER and the
time and date.
5. Set the unit to the Manual Mode by pressing
the AUTO/MAN key. A flashing Manual Fire
Rate
message will be displayed with the
present rate in %. Also, the MANUAL LED
will light.
4-2