Aerco Benchmark Series User Manual

INITIAL START-UP
4-3
4. Place the green ON/OFF switch in the OFF
position. Turn on AC power to the unit. The
temperature controller and annunciator
displays should light.
5. Set the temperature controller to manual
mode and change the firing rate to (Pct) to
0.0 percentage.
6. Place the green ON/OFF switch in the ON
position and change the firing rate (Pct) to
30%. The unit should begin its start
sequence and fire.
NOTE:
On initial start-up, or return to service from a
fault condition, a two-minute warm-up timer
is activated, preventing the BTU input from
exceeding 800,000 BTU/H although the
control signal may indicate a greater input.
7. Following the warm-up period, gradually
increase the firing rate to 100% and adjust
the supply gas pressure between 7.0 to 7.3”
water column.
8. Lower the firing rate to 40%. Insert the
combustion analyzer probe into the stack
and allow enough time for the combustion
analyzer to settle. Compare the measured
oxygen level to the oxygen range for inlet air
temperature in Table 1.
Combustion Oxygen Levels for a 40%
Firing Rate
Inlet Air
Temp
Oxygen
Carbon
Monoxide
80
°
F
7.2% <50ppm
70
°
F
7.6%
<50ppm
60
o
F
8.0%
<50ppm
50
o
F
8.4%
<50ppm
40
o
F
8.8%
<50ppm
30
o
F
9.2%
<50ppm
20
o
F
9.6%
<50ppm
10
o
F
10.0%
<50ppm
0
o
F
10.4%
<50ppm
-10
o
F
10.8%
<50ppm
-20
o
F
11.3%
<50ppm
Table 1
9. Adjust the differential regulator until the
Oxygen is within the specified range in
Table 1.
NOTE:
Adjust only the differential regulator at 40%
control signal; do not adjust the iris air
damper.
10. Once the oxygen level is within the specified
range at 40%, lower the firing rate to 20%.
11. Oxygen levels at the 20% firing rate should be
as shown in Table 2.
Combustion Oxygen Levels for a 20%
Firing Rate
Inlet Air
Temp
Oxygen
Carbon
Monoxide
80
°
F
12% or less
<100ppm
70
°
F
12% or less
<100ppm
60
o
F
12% or less
<100ppm
50
o
F
12% or less
<100ppm
40
o
F
12% or less
<100ppm
30
o
F
12% or less
<100ppm
20
o
F
12% or less
<100ppm
10
o
F
12% or less
<100ppm
0
o
F
12% or less
<100ppm
-10
o
F
12% or less
<100ppm
-20
o
F
12% or less
<100ppm
Table 2
12. Raise the firing rate to 100%. Gas pressure
should still be between 7.0 and 7.3” WC. If it
is not readjust as necessary.
13. Allow the combustion analyzer to settle.
Compare the measured oxygen level with
the levels in Table 3.
14. If the measured oxygen reading is within the
specified level in Table 3, no further
adjustment is necessary. If the measured
oxygen level is not with in specified range in
Table 3 adjust the iris damper as necessary
until the measured oxygen reading is within
specification.
Combustion Oxygen Levels for 100%
Firing Rate
Inlet Air
Temp
Oxygen
Carbon
Monoxide
80
°
F
4.4%
<100ppm
70
°
F
4.8% <100ppm

Aerco Benchmark Series Specifications

General

Model	Benchmark Series
Category	Boiler
Manufacturer	Aerco
Vent Material	Stainless Steel
Fuel Type	Natural Gas
Operating Pressure	160 psig
Control System	Aerco Control System
Heat Exchanger Material	Stainless Steel