4 propane combustion calibration – AERCO BMK 2000DF User Manual
Page 60

Benchmark 1500DF - 2000DF Boilers
CHAPTER 4 – INITIAL START-UP
Page 60 of 196
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913
OMM-0098_0A
04/01/2014
Ph.: 800-526-0288
GF-144
4.4 PROPANE COMBUSTION CALIBRATION
If the boiler is currently running Natural Gas, complete the instructions in section 4.5.1 to switch
the boiler fuel source from NATURAL GAS to PROPANE Gas.
The Benchmark boiler is combustion calibrated at the factory prior to shipping. This gas
pressure must be within the following ranges for each model of boiler at full fire:
Table 4-2: Nominal Gas Pressure – PROPANE
BMK Boiler Model
Nominal PROPANE Gas Pressure
BMK 1500DF
1.4” W.C. ±0.2” W.C.
BMK 2000DF
2.5” W.C. ±0.2” W.C.
Recalibration as part of initial start-up is necessary due to changes in the local altitude, gas BTU
content, gas supply piping and supply regulators. Combustion Calibration Test Data sheets are
shipped with each unit. These sheets must be filled out and returned to AERCO for proper
Warranty Validation.
It is important to perform the following procedure as outlined. This will keep readjustments to a
minimum and provide optimum performance.
The following Instructions for PROPANE combustion calibration apply to both BMK 1500DF and
BMK 2000DF model units.
PROPANE Combustion Calibration
1. Open the water supply and return valves to the unit and ensure that the system pumps
are running.
2. Open the PROPANE supply valve to the unit.
3. Set the control panel ON/OFF switch to the OFF position
4. Turn on external ac power to the unit. The display will show loss of power and the time
and date.
5. Set the unit to the manual mode by pressing the AUTO/MAN key. A flashing manual
valve position message will be displayed with the present position in %. Also, the
MANUAL
LED will light.
6. Adjust the air/fuel valve position to 0% by pressing the ▼ arrow key.
7. Ensure that the leak detection ball valve downstream of the SSOV is open.
8. Set the ON/OFF switch to the ON position.
9. Change the valve position to 30% using the ▲ arrow key. The unit should begin its start
sequence and fire.
10. Next, verify that the gas pressure downstream of the SSOV s set to the proper value,
listed in Table 4-2. If gas pressure adjustment is required, remove the brass hex nut on
the SSOV actuator to access the gas pressure adjustment screw (Figure 4-3, above).
Make gas pressure adjustments using a flat-tip screwdriver to obtain the proper gas
pressure.
11. Using the ▲ arrow key, increase the valve open position to 100%. Verify that the gas
pressure on the downstream side of the SSOV settles within the range listed in Table 4-2.
Readjust the gas pressure if necessary.