AERCO BMK 3.0 LN Dual-Fuel Series Gas Fired Low NOx Boiler System - Manual (Page 53)

SAFETY DEVICE TESTING
6-5
PARTIAL LEFT SIDE VIEW
BLOWER
AIR
INLET
BLOCKED
AIR INLET
SWITCH
AIR/FUEL
VALVE
MANUAL GAS
SHUTOFF VALVE
HANDLE
PROPANE
P
A
R
T
O
F
FR
A
M
E
G
A
S
IN
LE
TS
NATURAL GAS
S
S
O
V
s
(2
)
Figure 6-3
Manual Gas Shut-Off Valve Location
6.10 AIR FLOW FAULT TESTS
These tests check the operation of the Blower
Proof Switch and Blocked Inlet Switch shown in
Figure 6-3.
1. Disable the blower output drive voltage as
follows:
(a) Press the MENU key until CONFIGUR-
ATION MENU is displayed.
(b) Press the ▲ arrow key until the ANA-
LOG 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 execute an
IGNITION RETRY cycle by performing the
following steps:
(a) The unit will execute a 30 second re-
ignition delay and display WAIT RETRY
PAUSE.
(b) The unit will then execute a standard
ignition sequence and display WAIT
IGNITION RETRY.
4. The unit should perform two IGNITION
RETRY cycles and then shut down on the
third successive ignition attempt. The unit will
display AIRFLOW FAULT DURING PURGE.
5. Re-enable the blower output drive voltage by
performing the following steps:
(a) Press the MENU key until CONFIGUR-
ATION MENU is displayed.
(b) Press the ▲ arrow key until the ANA-
LOG 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.
6. Once the unit has proved flame, turn off the
blower 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 Fire Rate 0-10v.
9. Press the CLEAR button. The unit should
restart.
10. Next, check the Blocked Inlet Switch by first
noting the current position of the Iris Air
Damper and then closing the Damper to
position 8.
11. .The unit should shut down and again
display AIRFLOW FAULT DURING RUN.
12. Return the Iris Air Damper to its previous
setting.
13. Press the CLEAR button. The unit should
restart.
6.11 SSOV PROOF OF CLOSURE
SWITCH
This test can be performed when the unit is set
up to run on either natural gas or proane fuel.
Downstream SSOVs #1 (natural gas) and #3
(propane) shown in Figure 6-1 contain the proof