AERCO BMK 2.0 LN Natural Gas (SN G-11-1861 and above) - Manual (Page 87)

GF-123
Benchmark 2.0LN Low NOx Boiler
Chapter 7
OMM-0046_0E I nstallation, Operation and Maintenance Manual Maintenance
PR1 08/20/12 AERCO International Inc.● 100 Oritani Dr. ● Blauvelt, NY 10913. ● Ph: 800-526-0288 Page 87 of 170
7.4 COMBUSTION CALIBRATION & RSI REGULATOR ADJUSTMENT
The Combustion Calibration settings and RSI Regulator adjustment must be checked at the
intervals shown in Table 7-1 as part of the maintenance requirements. Refer to Chapter 4 for
combustion calibration instructions. Refer to paragraph 7.4.1, below, for RSI regulator test and
calibration instructions.
7.4.1 RSI Regulator Pressure
The BMK2.0LN unit has a RSI (Regulated Staged Ignition) system in the gas train that should
be pressure tested annually. If the pressure is above 5.0” w.c. or below 3.0” w.c., then the RSI
pressure regulator must be recalibrated per paragraph 7.4.1.2.
7.4.1.1 RSI Regulator Pressure Test
The RSI regulator test is performed as follows:
1. Ensure that gas supply shut-off valve upstream of the unit is still turned OFF.
2. Turn OFF electrical power to the system.
3. CLOSE the following valves in the unit’s gas train (refer to Figure 7-4):
4. RSI Gas Supply Valve
5. RSI Bleed-off Valve
6. Manual Shut-off Valve (between the Air/Fuel Valve and the SSOV).
7. Remove the pipe plug from the 1/4” NPT port on the outlet side of the RSI regulator and
insert a NPT-to-barbed adapter fitting (see Figure 7-4).
8. Attach one end of the plastic tubing to the barbed fitting and the other end to the 16” W.C.
manometer.
9. Remove the cap from the RSI Pressure Regulator and rotate the regulator adjustment
(beneath cap) counterclockwise (CCW) to its lowest possible pressure setting that will allow
the cap to be installed.
10. OPEN the main gas supply upstream of the unit.
11. Turn ON electrical power to the system.
12. Slowly OPEN the RSI Gas Supply Valve and observe the reading on the manometer. It
should have a reading of less than 8.0” w.c.
13. Start the boiler in MANUAL Mode. Observe the manometer pressure when the RSI solenoid
“clicks” open after purge. It should now provide a reading of less than 5.0” w.c., but not less
than 3.0” w.c..
14. Look into the observation port in the top head and ensure that you observe the orange glow
of the RSI flame during the ignition trial period.
15. If the pressure is within specifications, return the unit to service. Make sure that the unit is
operating in AUTO Mode. The “MAN” light in the upper left of the control box should NOT be
lit when in AUTO Mode.
16. If the RSI regulator is NOT within specifications, proceed to paragraph 7.4.1.2, RSI
Regulator Calibration, and initiate the pressure calibration procedures.