Watts Benchmark Aerco OMM-0122 - 5.7 FLAME FAULT TEST

Benchmark 750-3000 Boiler Installation & Startup Manual
SECTION 5 – SAFETY DEVICE TESTING
OMM-0121_D • GF-205 • 5/9/2019 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page 90 of 122
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 ON/OFF switch to the OFF position.
2. Place the unit in the MANUAL mode and set the valve position between 25% and 30%.
3. Close the manual gas shutoff valve located between the Safety Shut-O
ff Valve (SSOV)
and the Air/Fuel Valve, as shown on Figure 5-3a, 5-3b and 5-3c, above.
4. It may be necessary to jump out the High Gas Pressure switch.
5. Set the ON/OFF switch to the ON position to start the unit.
6. 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.
7. Open the valve previously closed in step 3 and press the CLEAR button.
8. Restart the unit and allow it to prove flame.
9.
Once flame is proven, close the manual gas valve located between the SSOV and the
Air/Fuel Valve (see Figure 5-3a, 5-3b or 5-3c, above).
10. The unit should shut down and do one of the following:
a) BMK 2500 & 3000 units: the unit will Lockout and FLDR (Flame Loss During Run)
will flash in the display.
b) BMK 750 – 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 gas 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.
11. Open the valve closed in step 9.
12. Press the CLEAR button. The unit should restart and fire.