AERCO BMK 3.0 LN Nat. Gas Jan 2009 - Manual (Page 36)

INITIAL START-UP
4-4
Figure 4-4
Iris Air Damper Location/Adjustment
NOTE
The remaining combustion calibration
steps utilize the Variable Frequency Drive
(VFD) located behind the front door of the
unit. The VFD controls will be used to
adjust the oxygen level (%) at firing rates
of 70%, 50%, 40%, 30% and 14% as
described in the following steps. These
steps assume that the inlet air
temperature is within the range of 50°F to
100°F.
16. Locate the Variable Frequency Drive (VFD)
behind the front door of the unit. Refer to the
VFD operating controls shown in Figure 4-5.
Figure 4-5
VFD Controls and Displays
17. Press the M (Menu) programming key on
the VFD.
18. Using the up (▲) arrow key, select VFD
parameter 65. The selected parameter will
appear in the left part of the display and the
frequency (Hz) will appear in the right part of
the display.
19. With the selected VFD parameter display
flashing, press the M key. Code will be
displayed, requesting the valid code to be
entered. Enter code 59 using the arrow
keys.
20. Press the M key again and observe the
frequency shown in the right part of the
display. The oxygen level at the 70% firing
rate should be as shown in the following
tabular listing. Also, ensure that the carbon
monoxide (CO) and nitrogen oxide (NOx)
readings do not exceed the values shown.
Combustion Oxygen Level at
70% Firing Rate
Oxygen %
± 0.2
Carbon
Monoxide NOx
6.0 % <100 ppm <30 ppm
21. If the oxygen level is not within the specified
range, adjust the level using the up (▲) and
down (▼) arrow keys on the VFD. Using the
up (▲) arrow key will increase oxygen level
and the down (▼) arrow key will decrease
the oxygen level.