Additional Faults Without Specific Fault Messages - Watts AERCO CFR 1500 Operation And Service Manual

SECTION 9 TROUBLESHOOTING

9.2 Additional Faults Without Specific Fault Messages

Refer to Table 9-2 to troubleshoot faults that occur without a specific fault message displayed.
TABLE 9-2: Boiler Troubleshooting with No Fault Message Displayed
Fault Probable Causes
1. Clogged/damaged Gas
Hard Light-Off
2. Defective Staged Ignition
1. Gas pressure going into unit
2. Damping Orifice not
Fluctuating Gas
Pressure
The following Unit Status messages are related to the CFR boiler's Stack Guard operation:
The Stack Guard temperature
Low Stack Temp
is below the Stack Guard Low
Shutdown
Limit
Stack Guard Sensor Stack guard sensor is not
Open installed.
Stack Guard Sensor Stack Guard Sensor is shorted
Short
Figure 9-1: SSOV Actuator with Gas Pressure Adjustment (SKP25)
•
Injector on Igniter-Injector
(Figure 8-1a through Figure
8-1c).
Solenoid (Figure 8-1a
through Figure 8-1c).
is fluctuating.
installed.
•
Corrective Action
1. Disconnect the Staged Ignition Assembly solenoid from
the Gas injector Tube of the Igniter-Injector (Figure 8-
1a through Figure 8-1c) and inspect Gas Injector to
ensure it is not clogged or damaged.
2. Close the Manual Shutoff Valve. Attempt to start the
unit and listen for a "clicking" sound that the Staged
Ignition Solenoid makes during Ignition Trial. If
"clicking" sound is not heard after 2 or 3 attempts,
replace the Staged Ignition Solenoid.
1. Stabilize gas pressure going into unit. If necessary,
troubleshoot Building Supply Regulator.
2. Check if the gas train is supposed to have a Damping
Orifice, and if so, ensure that it is installed in the SSOV
Actuator, as shown in Figure 10-1, below. For DBB Gas
Trains, the Damping Orifice is installed in the
downstream SSOV Actuator).
Check the system return water temperature. The required
minimum return water temperature is 120°F.
Ensure the stack guard sensor is installed in the starter
section and it is connected to the boiler wiring harness.
Check for a short in the wiring connection between
sensor and CFR boiler.
•