AERCO BMK 3.0 LN Natural Gas July 2011 - Manual (Page 36)

INITIAL START-UP
4-2
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.
UNIT
FRAME
EXHAUST
MANIFOLD
CONDENSATE
TRAP
DRAIN
HOSE
TO FLOOR
DRAIN
FLUE
VENT PROBE
PORT
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.
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
Valve Position message will be displayed
showing the present air/fuel valve % open
position. Also, the MANUAL LED will light.
6. Adjust the air/fuel valve position to 0% by
pressing the ▼ arrow key.
7. Ensure that the leak detection ball valve
downstream of the SSOV is open.
8. Set the ON/OFF switch to the ON position.
9. Change the valve position to 29% using the
▲ arrow key. The unit should begin its start
sequence and fire.