Flame Fault Test - Watts AERCO Benchmark BMK750 Operation And Service Manual

Benchmark with Edge [I]: Operation-Maintenance Manual
SECTION 5 – SAFETY DEVICE TESTING

5.7 FLAME FAULT TEST

Flame faults can occur during ignition or while the unit is already running. To simulate each of
these fault conditions, proceed as follows:
Flame Fault Test Instructions
1. Set the Controller's Enable/Disable switch to Disable.
2. On the Controller, go to:
3. Enable the Manual Run control.
4. Set the valve position between 25% and 30% using the + (Plus) and – (Minus) controls.
5. Close the gas train's Manual Shutoff valve located between the Safety Shut-Off Valve
(SSOV) and the Air/Fuel Valve, as shown on Figure 5-3a to 5-3c, above.
6. It may be necessary to jump out the High Gas Pressure switch.
7. Set the Controller's Enable/Disable switch to Enable to start the unit.
8. The unit should purge and light the Pilot flame and then shut down after reaching the main
Burner Ignition cycle and display Flame Loss During Ign.
9. Open the Manual Shutoff valve closed in step 5 and press the CLEAR soft key.
10. Restart the unit and allow it to prove flame.
11. Once flame is proven, close the Manual Shutoff valve located between the SSOV and the
Air/Fuel Valve (see Figure 5-3a to 5-3c, above).
12. The unit should shut down and do one of the following:
a. BMK750 – 2000 units: the unit will execute an IGNITION RETRY cycle by performing
the following steps:
•
The unit will execute a shutdown purge cycle for a period of 15 seconds and
display Wait Fault Purge.
•
The unit will execute a 30 second re-ignition delay and display Wait Retry Pause.
•
The unit will then execute a standard ignition sequence and display Wait Ignition
Retry.
•
Since the Manual Shutoff valve is still closed, the unit will fail the ignition retry
sequence. Therefore, it will shut down and display Flame Loss During Ign
following the IGNITION RETRY cycle.
b. BMK2500 – 3000 units: the unit will Lockout and Flame Loss During Run will flash in
the display.
13. Open the manual gas valve closed in step 11.
14. Press the CLEAR button. The unit should restart and fire.
OMM-0145_A99 • GF-218 •
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