Innovation Water Heaters Installation, Operation & Maintenance Manual
CHAPTER 4 – INITIAL START-UP
OMM-0078_0M
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
Page
59
of
216
GF-128
Phone: 800-526-0288
09/11/2015
NATURAL GAS Combustion Calibration -
Continued
21.
Once the oxygen level is within the specified range at 100%, press the
ENTER
key to store
the selected blower output voltage for the 100% valve position. Record all readings on the
Combustion Calibration Sheets provided.
22.
Repeat steps 16 through 21 for the following valve positions (see NOTE below):
80%, 60%, 50%, 40%, 30%, 20%, 16%
NOTE
If NOx readings exceed the target values shown (<20 ppm), increase the O
2
level up to 25% higher than the listed calibration range shown in the table.
Record the increased O
2
value on the Combustion Calibration sheet.
Combustion Calibration Readings
Valve
Position
Oxygen (O
2
) %
± 0.25%
Nitrogen
Oxide (NOx)
Carbon
Monoxide (CO)
Flame
µA
100%
6.0%
<20 ppm
<100 ppm
> 6
80%
6.5%
<20 ppm
<100 ppm
> 6
60%
6.5%
<20 ppm
<100 ppm
> 6
50%
7.0%
<20 ppm
<100 ppm
> 6
40%
7.0%
<20 ppm
<100 ppm
> 6
30%
7.5%
<20 ppm
<100 ppm
> 5
20%
7.0%
<20 ppm
<100 ppm
> 4
16%
6.0%
<20 ppm
<100 ppm
> 2
23.
If the oxygen level at the 16% valve position is too high and the Blower voltage is at the
minimum value, you can adjust the idle screw (TAC valve), which is recessed in the top of
the Air/Fuel Valve. 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% down to 16%
after making a change to the idle screw (TAC valve).
Figure 4-5. TAC Valve (Idle Screw) Adjustment
This completes the NATURAL GAS combustion calibration procedure.
TAC VALVE
IDLE SCREW
