Air Flow Fault Tests; Blower Proof Switch Test; Blocked Inlet Switch Test - Aerco BENCHMARK 2500DF User Manual

Benchmark 2500DF-3000DF Installation, Operation & Maintenance Manual

6.8 AIR FLOW FAULT TESTS

These tests check the operation of the Blower Proof Switch and Blocked Inlet Switch shown in Figure 6-3.

6.8.1 Blower Proof Switch Test

1. Disable the blower output drive voltage as follows:
(a) Press the MENU key until CONFIGURATION MENU is displayed.
(b) Press the ▲ arrow key until the ANALOG OUTPUT function is displayed, then
press the CHANGE key.
(c) Press the ▼ arrow key until OFF is displayed, then press the ENTER key.
2. Start the unit in the Manual Mode at a valve position between 25% and 30%.
3. The unit should shut down and lockout, showing AIRFLOW FAULT DURING PURGE in
the display.
4. The unit should perform one IGNITION RETRY cycle and then shut down, since the
blower is disabled. The unit will then display AIRFLOW FAULT DURING PURGE.
5. Re-enable the blower output drive voltage by performing the following steps:
(a) Press the MENU key until CONFIGURATION MENU is displayed.
(b) Press the ▲ arrow key until the ANALOG OUTPUT function is displayed, then
press the CHANGE key.
(c) Press the ▲ arrow key until VALVE POSITION 0-10V is displayed, then press the
ENTER key.
(d) Press the CLEAR button to clear the airflow fault.
6. Once the unit has proved flame, turn off the blower again by going to the Configuration
Menu, Analog Output menu item and select OFF.
7. The Blower Proof Switch will open and the blower should stop. The unit should shut
down and display AIRFLOW FAULT DURING RUN.
8. Go to the Configuration Menu, Analog Output item and select VALVE POSITION 0-10v.

6.8.2 Blocked Inlet Switch Test

This test will be run in simulated fire mode, with the Blocked Inlet Switch isolated from the rest of the
control circuitry.
1. Turn off the main ON/OFF switch on the front of the Control Panel.
2. For units that get combustion air from a Combustion Air Duct, remove that duct, located
on the rear panel of the boiler (see Figure 6.4, below). For units that have an air filter in
place of a Combustion Air Duct (not shown), remove the air filter.
Page 84 of 234
05/21/2014
CHAPTER 6 – SAFETY DEVICE TESTING
Blower Proof Switch Test
Blocked Inlet Switch Test
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913
Phone: 800-526-0288
OMM-0099_0A
GF-145