Low Gas Pressure Test - Watts Aerco BENCHMARK 750 User Manual

Benchmark 750 – 1000 Boiler User Manual - INTERNATIONAL

6.2 LOW GAS PRESSURE TEST

To simulate a low gas pressure fault, refer to Figure 6-1a and perform the following steps:
SSOV
1/4" NTP PLUG
(Install manometer here for
LOW Gas Pressure Test)
1. Close the leak detection ball valve located at the Low Gas Pressure switch.
2. Remove the 1/4" NPT plug from the ball valve at the Low Gas Pressure switch.
3. Install a 0 - 16" W.C. (0 – 4.0 kPa) manometer or gauge where the 1/4" plug was
removed.
4. Slowly open the ball valve near the Low Gas Pressure switch.
5. Place the unit in MANUAL mode and adjust the Air/Fuel Valve position (% open) between
25% and 30%.
6. While the unit is firing, slowly close the external manual gas shut-off valve.
7. The unit should shut down and display a GAS PRESSURE fault message at approximately
2.6" W.C. (648 Pa) for both 750 & 1000 units.
8. Fully open the external manual gas shut-off valve and press the CLEAR button on the
Control Box.
9. The fault message should clear and the FAULT indicator should go off. The unit should
restart.
10. Upon test completion, close the ball valve and remove the manometer. Replace the 1/4"
NPT plug removed in step 2.
Page 72 of 170
11/03/2016
CHAPTER 6 – SAFETY DEVICE TESTING
TO AIR/FUEL
VALVE
Figure 6-1a: Low Gas Pressure Test
Low Gas Pressure Fault Test
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913
Ph.: 800-526-0288
MANUAL SHUT-OFF
VALVE
HIGH GAS PRESSURE SWITCH
HIGH GAS PRESSURE
LEAK DETECTION BALL VALVE
LOW GAS PRESSURE SWITCH
LOW GAS PRESSURE
LEAK DETECTION BALL VALVE
(shown open)
GAS INLET
OMM-0119_0A
GF-130-I