Watts AERCO Benchmark BMK5000 Operation And Service Manual page 135

Benchmark Platinum-Edge [ii]: Operation-Service Manual
SECTION 6 – TROUBLESHOOTING
TABLE 10-1: Boiler Troubleshooting Procedures
Fault Probable Causes
Worn Flame Detector or cracked ceramic.
1.
Defective Regulator.
2.
FLAME LOSS
Poor combustion calibration.
DURING RUN 3.
Debris on burner.
4.
Blocked condensate drain.
5.
1. The Heat Demand Relays on the
HEAT
Ignition/Stepper (IGST) board failed to activate
DEMAND
when commanded.
FAILURE
Relay is activated when not in Demand.
2.
Poor combustion calibration.
1.
HIGH EXHAUST
TEMPERATURE
Carboned heat exchanger due to incorrect
2.
combustion calibration.
Incorrect supply gas pressure.
1.
Defective SSOV Actuator.
2.
HIGH GAS
PRESSURE
Defective High Gas Pressure switch.
3.
OMM-0137_J • Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST
12/20/2022
Corrective Action
Remove and inspect the Flame Detector for signs of wear or
1.
cracked ceramic. Replace if necessary.
Check gas pressure readings using a gauge or manometer into
2.
and out of the Air/Fuel Valve to ensure that the gas pressure into
and out of the valve is correct.
Check combustion calibration using the procedures in Section 4.4:
3.
Combustion Calibration of this guide.
Remove the burner and inspect for any carbon build-up or debris.
4.
Clean and reinstall.
Remove blockage in condensate drain.
5.
1. Press CLEAR button and restart the unit. If the fault persists,
replace Ignition/Stepper (IGST) Board.
Defective relay. Replace IGST Board.
2.
Check combustion calibration using procedures in Section 4.4:
1.
Combustion Calibration of this guide.
If exhaust temperature is greater than 200
2.
combustion calibration. Calibrate or repair as necessary.
Check to ensure gas pressure at inlet of SSOV does not exceed
1.
14" W.C. (3.49 kPa).
If gas supply pressure downstream of SSOV Actuator cannot be
2.
lowered to the range specified in Table 4-1 (Natural Gas) or Table
4-4 (Propane) in Section 4.4: Combustion Calibration of this guide;
the SSOV Actuator may be defective.
Remove the leads from the High Gas Pressure switch. Measure
3.
continuity across the common (C) and normally closed (NC)
terminals with the unit not firing. Replace the switch if continuity
does not exist.
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