AERCO BMK 1.5 LN Dual Fuel Jan 2009 - Manual (Page 32)

INITIAL START-UP
5. Attach one end of the plastic tubing to the
barbed fitting and the other end to the 16
inch W.C. manometer.
PROPANE
SSOV NATURAL
GAS SSOV
NATURAL GAS
HIGH GAS
PRESSURE
SWITCH
PROPANE
HIGH GAS
PRESSURE
SWITCH
PROPANE PRESSURE
REGULATOR
FEEDBACK LINE
NATURAL GAS
PRESSURE
REGULATOR
FEEDBACK LINE
NATURAL
GAS INLET
PROPANE
INLET
1/8" NPT PLUG
(INSTALL MANO-
METER HERE)
LEAK DETECTION
BALL VALVE
Figure 4-1.
1/8 Inch Gas Plug Location
4.2.3 Accessing the Vent Probe Port
The unit contains NPT plug on the exhaust
manifold at the rear of the unit as shown in
Figure 4-2. 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.
Figure 4-2
Analyzer Probe Hole Location
IMPORTANT
For Dual Fuel units, perform the natural
gas combustion calibration procedures in
paragraph 4.3 before performing the
propane combustion calibration proce-
dures in para. 4.4.
Refer to Appendix K for switchover
instructions when changing from Natural
Gas to Propane or from Propane to
Natural Gas.
4.3 NATURAL GAS COMBUSTION
CALIBRATION
The Benchmark 1.5LN Dual-Fuel 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.
3. Open the water supply and return valves to
the unit and ensure that the system pumps
are running.
4. Open the natural gas supply valve(s) to the
unit.
5. Set the control panel ON/OFF switch to the
OFF position.
6. Turn on external AC power to the unit. The
display will show LOSS OF POWER and the
time and date.
7. 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.
8. Adjust the fire rate to 0% by pressing the ▼
arrow key.
9. Ensure that the leak detection ball valve
down-stream of the Natural Gas SSOV
(Figure 4-1) is open.
10. Ensure that the Fuel Selector Switch (Figure
4-3) is in the NATURAL GAS position.
4-2