AERCO BMK 3.0 LN Nat. Gas June 2010 - Manual (Page 52)

SAFETY DEVICE TESTING
6-6
4. Initiate a unit start sequence.
5. The unit should begin it’s start sequence,
then shut down and display PRG SWITCH
OPEN DURING PURGE.
STEPPER
MOTOR DIAL
17
2 17
1
16
9
17
0
IGNITION
POSITION
SWITCH
PURGE
POSITION
SWITCH
AIR
IN
TO
BLOWER
6. Replace the wire on the Purge Switch and
depress the CLEAR button. The unit should
restart.
6.11 IGNITION SWITCH OPEN DURING
IGNITION
The Ignition Switch (and the Purge Switch) is
located on the Air/Fuel Valve. To check the
switch, proceed as follows:
1. Set the unit’s ON/OFF switch to the OFF
position.
2. Place the unit in Manual Mode and set the
valve position between 25% and 30%.
3. Remove the Air/Fuel Valve cover (Figure
6-5) by rotating the cover counterclockwise to
unlock and lift up to remove.
Figure 6-6
Air/Fuel Valve Purge and Ignition Switch
Locations
4. Remove one of the two wires (#169 or #170)
from the Ignition Switch (Figure 6-6).
5. Initiate a unit start sequence.
6. The unit should begin its start sequence and
then shut down and display IGN SWITCH
OPEN DURING IGNITION.
6.12 SAFETY PRESSURE RELIEF
VALVE TEST
Test the safety Pressure Relief Valve in
accordance with ASME Boiler and Pressure
Vessel Code, Section VI.
7. Replace the wire on the Ignition Switch and
press the CLEAR button. The unit should
restart.
AIR/FUEL VALVE COVER
(ROTATE CCW TO REMOVE)
Figure 6-5
Air/Fuel Valve Cover Location