2 front refractory removal & replacement – AERCO BMK 6000 Dual Fuel User Manual
Page 112
Benchmark 6000 DF Installation, Operation & Maintenance Manual
CHAPTER 7 – MAINTENANCE
Page 112 of 219
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913
OMM-0096_0B
03/21/2014
Ph.: 800-526-0288
GF-141
THE HEAT EXCHANGER INSULATION UTILIZES CERAMIC FIBER
MATERIAL. WEAR A FITTED NIOSH-APPROVED PARTICULATE
RESPIRATOR (3M N95 OR EQUIV.) WHEN SERVICING THE HEAT
EXCHANGER AND BURNER ASSEMBLIES. AT HIGH TEMPERATURES,
CERAMIC FIBERS CAN BE CONVERTED TO CRYSTALINE SILICA
FIBERS WHICH HAVE BEEN IDENTIFIED AS CARCINOGENIC WHEN
INHALED.
7.8.2 Front Refractory Removal & Replacement
As previously mentioned in section 7.8, it is much easier to remove the rear refractory to inspect
the combustion chamber of the unit. However if the front refractory must be removed, it must be
replaced with a new refractory, part no. 83028.
Front refractory removal and replacement requires that the Burner, Blower and Air/Fuel Valve
assemblies be removed to access and remove the front refractory. This accomplished by
performing the following steps:
Front Refractory Replacement Procedure
1.
Turn off gas and electrical power to the unit.
2.
Follow the instructions in section 7.7 for blower and Burner assembly removal. The
instructions in section 7.7 include removal of the Main Flame Detector, Pilot Burner
assembly and two Pilot Flame Detectors.
3.
Disconnect the wires from the thermal switch on the upper portion of the front (Burner)
plate.
4.
Remove all bolts EXCEPT for the one at the top of the plate.
5.
While supporting the plate, remove the remaining bolt and slide the plate outward. The
front refractory and Burner Shield should slide out of the combustion chamber with the
plate.
6.
Spray the refractory with a water mist to reduce airborne dust.
7.
Remove the three (3) 10-32 screws securing the Burner Shield to the Burner Plate.
8.
Place the Burner Shield on a flat surface with the three tabs facing upward.
9.
Straighten the 90º bend in each tab so they are even with the sides of the Burner Shield
(Figure 7-9).
10.
Place the new refractory (part no. 83028) and shield, blanket-side down, onto the plate.
Align the holes for mounting.
11.
Place 1” diameter wood or metal dowels into the 2 large holes on the front plate.
12.
Slide the refractory, blanket-side up, over the shield. Align the 3 holes in the refractory with
the 3 tabs on the Burner Shield. Bend the tabs 90º and align them with the 3 tapped holes
in the front plate.
WARNING