AERCO BMK 2.0 LN Natural Gas (SN G-11-1861 and above) - Manual (Page 91)

GF-123
Benchmark 2.0LN Low NOx Boiler
Chapter 7
OMM-0046_0E I nstallation, Operation and Maintenance Manual Maintenance
PR1 08/20/12 AERCO International Inc.● 100 Oritani Dr. ● Blauvelt, NY 10913. ● Ph: 800-526-0288 Page 91 of 170
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
(Figures 7-6).
11. Remove the 10-32 x 1/2" long grounding screw from the burner plate (Figures 7-4).
12. Disconnect the gas train from the air/fuel valve by removing the four (4) 1/2” bolts and nuts
(Figure 7-5).
13. Disconnect the inlet air flex hose from the air/fuel valve by loosening the hose clamp.
14. Remove the six (6) 1/4-20 hex nuts and flat washers securing the blower to the burner plate
(Figure 7-6).
15. Remove the blower and air/fuel valve from the burner plate by lifting straight up. Also,
remove the blower gasket, which will be replaced with a new gasket.
16. Remove the eight (8) 3/8-16 nuts from the burner flange (Figure 7-5) using a 9/16” wrench.
BLOWER
PROOF
SWITCH
BLOCKED
INLET
SWITCH
AIR/FUEL
VAVLE
STAGED
IGNITION
ASSEMBLY
FLAME
DETECTOR
BURNER
PLATE
HEX NUTS &
WASHERS (6)
BLOWER
GASKET
IGNITOR-
INJECTOR
BURNER
BLOWER
BURNER
GASKET
BURNER
GASKET
Figure 7-6: Burner Assembly Exploded View
NOTE
The burner assembly is heavy, weighing approximately 30 pounds.
17. Remove the burner assembly from burner flange by pulling straight up.
18. Remove and replace the two (2) burner gaskets.