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Benchmark 750-3000 Boiler Operation & Maintenance Manual
SECTION 4 – MAINTENANCE
OMM-0122_D
•
GF-206
•
5/9/2019
Technical Support
•
(800) 526-0288
•
Mon-Fri, 8 am - 5 pm EST Page 43 of 164
Igniter-Injector Maintenance Procedure Instructions
Figure 4-2c: BMK 2500/3000 Igniter-Injector & Flame Detector Mounting Details
5. Next, loosen and remove the igniter-injector from the burner plate using a 1" open-end
wrench.
6. Check the igniter-injector for evidence of erosion or carbon build-up. If there is evidence of
substantial erosion or carbon build-up, the igniter-injector should be replaced. If carbon
build-up is present, clean the component using fine emery cloth. Repeated carbon build-up
is an indication that the combustion settings of the unit should be checked. To review
combustion calibration procedures, refer to Section 4.4 of the
Benchmark 750 – 3000
Installation and Startup Guide
, OMM-0121 (GF-205).
7. Prior to reinstalling the igniter-injector, apply a high temperature, conductive, anti-seize
compound to the threads.
8. Reinstall the igniter-injector in the burner plate using 1 to 3 indexing washers, as needed,
so that when the igniter-injector is tightened, its injector tube will be positioned within the
approximately 120° arc shown in Figure 4-3a through 4-3c, below. Note, the recommended
injection tube positioning differs for the positioning recommended in the past.
9. Torque the igniter-injector to
170 - 180 in-lbs (19.2 – 20.3 Nm). DO NOT over tighten
.
NOTE:
If replacement igniter-injector (Kit P/N
58023
) is being installed, a compression nut
containing a built-in ferrule and 3 indexing washers are included with the kit.
10. Connect the staged ignition assembly to the gas injector tube of the igniter-injector by
securing the compression nut to the elbow of the staged ignition assembly.
11.
Reconnect the igniter-injector cable.
12.
Reinstall the shroud on the unit.
STAGED IGNITION
SOLENOID
FLAME
DETECTOR &
GASKET
FLAME
OBSERVATION
PORT
INJECTOR-IGNITOR
ASSY WITH INDEXING
(CLOCKING) WASHERS
(0-3 as needed)
O2 SENSOR
& WASHER
FLEX GAS
HOSE NIPPLE
COMPRESSION
FITTING &
ELBOW
BURNER PLATE
FLANGE
BLOWER
PLENUM