Blocked Inlet Switch Test - Watts AERCO Benchmark BMK5000 Operation And Service Manual

Benchmark Platinum-Edge [ii]: Operation-Service 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. Set the Controller's Enable/Disable switch to Disable.
2. Remove the air filter(s) (see Figure 5-6a, 5-6b or 5-6c, 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) Create a connector similar to the one shown below and connect it to the Flame
Detector's black connector boot. Keep the alligator clip away from bare metal parts
until step 4b.
CONNECTOR
Figure 5-8: Connecting the Flame Signal Generator
4. On the Controller, go to:
in Manual Mode, then complete the following:
a) Ramp the boiler up to 100% fire rate and then set the Controller's Enable/Disable
switch to Enable.
b) When the 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
Controller displays Flame Proven and begins 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-0137_J •
12/20/2022
FLAME DETECTOR
CONNECTOR BOOT
Main Menu → Diagnostics → Manual Run
Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST
TO WIRE HARNESS
and then put the unit
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