AERCO BMK 2000DF - Manual (Page 96)

Benchmark 1500DF - 2000DF Boilers
CHAPTER 7 – MAINTENANCE
Page 96 of 196 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 OMM-0098_0A
04/01/2014 Ph.: 800-526-0288 GF-144
7.6 BURNER ASSEMBLY INSPECTION
The burner assembly is located at the top of the unit's heat exchanger. The burner assembly
may be hot. Therefore, allow the unit to cool sufficiently before removing the burner assembly.
NOTE
In order to do this procedure most efficiently with a minimum of
steps, a simple support rig has been designed to hold up the
blower and Air/Fuel Valve assembly while the blower plenum is
removed to allow the burner assembly to be removed for
maintenance. Using this support will relieve the blower’s weight
from bearing down upon the connection to the gas train. This
support rig prevents having to dismantle the entire blower and A/V
Valve assembly from the gas train. The support rig is available as
an after-market part.
The following parts will be required for reassembly after burner inspection:
Part No. Description
88183 Burner Upper Release Gasket (1 each)
81166 Burner Gasket (1 each)
81186 Burner Lower Release Gasket (1 each)
81048 Flame Detector Gasket (1 each)
To inspect or replace the burner assembly, proceed as follows:
Burner Assembly Inspection and Maintenance Procedures
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. Retrieve the blower support rig and attach it to the blower and unit as described in the
instructions provided with the rig.
10. Loosen and remove the four 5/16x1-3/4” bolts, washers, and nuts from the burner plenum
where it is attached to the blower (see Figure 7-4a & 7-4b).