User Manual

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.
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
4.3 NATURAL GAS COMBUSTION
CALIBRATION
The Benchmark 1.5LN 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.
6. Adjust the fire rate to 0% by pressing the ▼
arrow key.
7. Ensure that the leak detection ball valve
down-stream of SSOV No. 2 is open.
8. Set the ON/OFF switch to the ON position.
9. Change the fire rate to 29% using the ▲
arrow key. The unit should begin its start
sequence and fire.
10. Next, verify that the gas pressure
downstream of the SSOV is 3” W.C. for both
FM and IRI gas trains. If gas pressure
adjustment is required, remove the brass
hex nut on the downstream SSOV actuator
(IRI gas train) containing the gas pressure
regulator (Figure 4-3). Make gas regulator
adjustments using a flat-tip screwdriver to
obtain 3” W.C.
4-2