Blocked Inlet Switch Test - Watts Aerco Benchmark OMM-0116 Installation And Start-Up Manual

Benchmark 750-3000 Installation & Startup Manual
SECTION 5 – SAFETY DEVICE TESTING

5.8.2 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.
Blocked Inlet Switch Test Instructions
1. Turn the main ON/OFF switch on the C-More Controller to the OFF position.
2. Remove the air filter (see Figure 5-6a or 5-6b, above).
WARNING!
The blower suction is very strong and can pull nearby objects into the blower's fan blades.
Do NOT allow anything to be pulled into the blower! Do not wear anything that could get
caught and pull you into the blower.
3. Turn off the gas supply ball valve to the boiler and then complete the following steps:
a) Use jumper wires to jump out the Low Gas Pressure switch and the Blower Proof
switch.
b) Remove the black connector boot from the Flame Detector.
c) Connect the Flame Signal Generator to the black connector boot.
FLAME SIGNAL GENERATOR
Figure 5-8: Connecting the Flame Signal Generator
d) Keep the alligator clip away from bare metal parts until step 4c.
4. Complete the following with the boiler operating in MANUAL mode:
a) Ramp the boiler up to 100% fire rate and then turn the main ON/OFF switch on the C-
More Controller to the ON position.
b) Push the BACK button three (3) times to return to the upper level menu.
c) When the C-More Controller gets into the ignition phase, it will show IGNITION
TRIAL. At that point attach the alligator clip (see Figure 5-8) to any bare metal
surface or ground. The C-More Controller display should now show FLAME
PROVEN and begin to ramp up to 100% fire rate. Note that no gas or flame is
present in the boiler at this time.
5. Wait for the boiler to ramp up to at least 90% before continuing.
6. Cover the combustion air inlet opening with a solid, flat object, such as a piece of thick
plywood or a thick metal plate.
7. The unit should shut down and display AIRFLOW FAULT DURING RUN. This step
confirms proper operation of the Blocked Inlet switch.
8. Remove the cover from the air inlet opening and reinstall the Combustion Air Duct or air
filter.
9. Remove the jumper wires installed in step 3 and replace the black connector boot on the
Flame Detector.
10. Press the CLEAR button. The unit should restart.
• •
OMM-115_D GF-200 5/9/2019
FLAME DETECTOR
CONNECTOR BOOT
TO WIRE HARNESS
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