AERCO BMK 1000 - Manual (Page 94)

Benchmark 750/1000 Boiler Installation, Operation & Maintenance Manual
CHAPTER 7 – MAINTENANCE
Page 94 of 192 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 OMM-0082_0J
05/21/2014
Ph.: 800-526-0288
GF-130
To inspect or replace the burner assembly, proceed as follows:
Burner Assembly Inspection
1. Set the ON/OFF switch on the control panel, to the OFF position. Disconnect AC power
from the unit and turn off the gas supply.
2. Remove the top shroud from the unit by grasping the top handle and lifting straight up.
This will disengage the shroud from the four (4) pins in the side panels.
3. Disconnect the lead wire from the flame detector installed on the burner plate. See Figure
7-2.
4. Remove the two (2) screws securing the flame detector to the plate. The flame detector is
secured to the burner plate with one (1) #10-32 screw and one (1) #8-32 screw.
5. Remove the flame detector and gasket from the burner plate.
6. Disconnect the cable from the igniter-injector.
7. Using a 7/16” open-end wrench, disconnect the compression nut securing the gas
injector tube of the igniter-injector to the elbow of the staged ignition assembly (see
Figure 7-2). Disconnect the staged ignition assembly from the igniter-injector.
8. Next, loosen and remove the igniter-injector from the burner plate using a 1" open-end
wrench.
9. Disconnect the unit wiring harness connectors from the air/fuel valve and blower motor.
10. Disconnect the wire leads connected to the blower proof switch and blocked inlet switch
(Figure 7-4 and Figure 7-5).
11. Disconnect the gas train from the air/fuel valve by removing the four (4) 1/2” bolts and
nuts (Figure 7-4).
12. Disconnect the flex hose from the air/fuel valve by loosening the hose clamp.
13. Remove the four 5/16-18 hex head screws securing the blower to the burner plate
(Figure 7-5).
14. Remove the blower and air/fuel valve from the burner plate by lifting straight up. Also,
remove the blower gasket.
15. Remove the eight (8) 3/8-16 nuts from the burner flange (Figure 7-4) using a 9/16”
wrench.