Centurion Water Heater- Edge [ii]: Install-Operation-Service
SECTION 5: INITIAL START-UP
OMM-0153_A
• 8/25/2022 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page 45 of 131
Figure 5-4: Gas Pressure Adjustment Screw and TAC Screw Location
W A R N I N G :
Combustion calibration and O
2
Trim can both alter the voltage sent to the blower (Calibration
voltages), and thus interfere with each other. If O
2
Trim is enabled, and a change is made to
any calibration point during combustion calibration, you must make a corresponding change
to the O2 Target, O2 Lower Limit and O2 Upper Limit in
Main Menu
→
Advanced Setup
→
Performance
→
O2 Trim
→
O2 Trim Parameters
(see Section 9.3
–
O2 Sensor
Calibration
). Failing to make the change in O
2
levels per the new combustion calibration
means it may ignore the calibration value and adjust the O
2
to the O
2
Trim value instead.
5.3.1 Instructions For Combustion Calibration
1.
Ensure the Edge Controller’s Enable/Disable switch is set to
Disable
.
2. Open water supply and return valves to unit and ensure system pumps are running.
3. Open the
NATURAL GAS
supply valve to the unit.
4. Turn external AC power to the unit
ON
.
5. Go to:
Main Menu
→
Calibration
→
Manual Combustion
; if necessary, enter a
technician level password.
6. After the first
Manual Combustion Calibration
screen appears:
•
Verify incoming (upstream) gas pressure is within the allowable range (Section 2.8.1).
•
Connect gas manometer to upstream side of gas train’s SSOV (Section 5.2.2) and
connect the Combustion Analyzer (Section 5.2.3).
•
Ensure heating loop is capable of dissipating sufficient heat at full fire. In addition, if
your unit is running O
2
Trim, you must turn that feature OFF before continuing; O
2
Trim
will interfere with combustion calibration.
Figure 5-5: First Manual Combustion Calibration Screen
