Low Water Level Fault Test - Aerco BENCHMARK 2500DF User Manual

Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual
High Gas Pressure Test (Propane and Natural Gas)
1. Remove the 1/4" plug from the appropriate ball valve (Natural Gas or Propane) at the
associated high gas pressure switch as shown in Figure 6-1B.
2. Install a 0 – 16" W.C. manometer (or W.C. gauge) where the 1/4" plug was removed.
3. Slowly open the ball valve near the high gas pressure switch.
4. Start the unit in Manual mode at a valve position (firing rate) between 25 and 30%.
5. With the unit running, monitor the gas pressure on the manometer installed in step 2 and
record the gas pressure reading.
6. Slowly increase the gas pressure using the adjustment screw on the associated SSOV
(see Figure 6-1B).
7. The unit should shut down and display a GAS PRESSURE FAULT fault message (FAULT
indicator also starts flashing) when the gas pressure exceeds the following:
• BMK3000 DF = Approx. 6.6" W.C. for Natural Gas and 2.6" W.C. for Propane Gas.
• BMK2500 DF = Approx. 7.0" W.C. for Natural Gas and 3.0" W.C. for Propane Gas.
8. Reduce the gas pressure back to the value recorded in step 5. This pressure should be
within the following ranges:
• BMK3000 DF = Approx. 6.0" W.C. (± 0.2") for Natural Gas and 1.6" W.C. (± 0.2"
W.C.). for Propane Gas.
• BMK2500 DF = Approx. 6.0" W.C. (± 0.2") for Natural Gas and 2.0" W.C. (± 0.2" W.C.)
for Propane Gas.
9. Press the CLEAR button on the Control Box to clear the fault.
10. The fault message should clear and the FAULT indicator should go off. The unit should
restart.
11. Upon test completion, close the ball valve and remove the manometer. Replace the 1/4"
plug removed in step 1.

6.4 LOW WATER LEVEL FAULT TEST

To simulate a low water level fault, proceed as follows:
1. Set the ON/OFF switch to the OFF position
2. Close the water shut-off valves in the supply and return piping to the unit.
3. Slowly open the drain valve on the rear of the unit. If necessary the unit's relief valve may
be opened to aid in draining.
4. Continue draining the unit until a LOW WATER LEVEL fault message is displayed and the
FAULT indicator flashes.
5. Place the unit in the Manual Mode and raise the valve position above 30%.
6. Set the ON/OFF switch to the ON position. The READY light should remain off and the
unit should not start. If the unit does start, shut the unit off immediately and refer fault to
qualified service personnel.
7. Close the drain and pressure relief valve used in draining the unit.
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05/21/2014
CHAPTER 6 – SAFETY DEVICE TESTING
Low Water Level Fault
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913
Phone: 800-526-0288
OMM-0099_0A
GF-145