![background image](http://html1.mh-extra.com/html/watts/aerco-benchmark-omm-0136/aerco-benchmark-omm-0136_operation-and-service-manual_4051813050.webp)
Benchmark Platinum-Edge [II]: Operation-Service Manual
SECTION 4
– INITIAL START-UP
OMM-
0137_E • GF-211 • 12/13/2019 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page
50
of
153
PROPANE Combustion Calibration Instructions
TABLE 4-6b: PROPANE Final Valve Positions: BMK5000 & 6000
Valve Position
Oxygen (O
2
) %
Nitrogen Oxide
(NO
x
)
Carbon
Monoxide (CO)
Single-Fuel
Dual-Fuel
BMK5000
70%
70%
5.5% ± 0.5%
<100 ppm
<150 ppm
50%
50%
5.5% ± 0.5%
<100 ppm
<150 ppm
40%
40%
5.5% ± 0.5%
<100 ppm
<150 ppm
30%
30%
5.5% ± 0.5%
<100 ppm
<150 ppm
18%
18%
6.0% ± 1.0%
<100 ppm
<150 ppm
BMK6000
70%
85%
5.5% ± 0.5%
<100 ppm
<150 ppm
50%
65%
5.5% ± 0.5%
<100 ppm
<150 ppm
40%
45%
5.5% ± 0.5%
<100 ppm
<150 ppm
30%
30%
5.5% ± 0.5%
<100 ppm
<150 ppm
18%
18%
6.0% ± 1.0%
<100 ppm
<150 ppm
NOTE
:
If NOx readings exceed the target values in Table 4-6a and 4-6b, increase the O
2
level up to
1% higher than the listed calibration range shown in the table. Record the increased O
2
value
on the Combustion Calibration sheet.
26. If the oxygen level at the lowest valve position is too high, and the Blower voltage is at the
minimum value, you can adjust the TAC screw, which is recessed in the top of the Air/Fuel
Valve (see Figure 4-3). Rotate the screw 1/2 turn
clockwise
(CW)
to add fuel and reduce
the O
2
to the specified level. Recalibration MUST be performed again from 60% or 50%
down to the lowest valve position after making a change to the TAC screw.
This completes the PROPANE gas combustion calibration procedure.
4.5 REASSEMBLY
Once the combustion calibration adjustments are properly set, the unit can be reassembled for
service operation.
Reassembly Instructions
1. Set the Enable/Disable switch in the
Disable
position.
2. Disconnect AC power from the unit.
3. Shut off the gas supply to the unit.
4. Remove the manometer and barbed fittings and reinstall the NPT plug using a suitable
pipe thread compound.
5.
Remove the combustion analyzer probe from the 1/4” vent hole in the exhaust manifold
and then replace the 1/4” NPT plug in the vent hole.