11
®
FIGURE 10.
ALIGNMENT AND ADJUSTMENT
The following procedures are recommended to ensure optimum flame detection and discrimination.
Flame discrimination is the ability to see only one burner or one pilot with other burners or pilots
operating nearby. These procedures should be used whenever parts are replaced, when the scanner
has been moved, when the flame shape is altered (additional fuels, new burners, burner/register mod-
ifications) as well as on all new installations.
Pilot Flame Scanner
1.
Apply power to scanner.
2.
Start pilot.
3.
Adjust scanner sighting to detect pilot flame in the manner shown in Figure 4.
4.
When flame is properly sighted, the flame signal relay should energize and the internal LED
should be indicating Flame Signal (see table 3).
5.
Make sure that the scanner does not respond to the ignition spark. This is accomplished by cut-
ting off the fuel to the pilot and attempting to start the pilot using the spark igniter. If the system
responds to the spark, the sighting should be realigned.
Main Flame Scanner
1.
Apply power to scanner.
2.
Start pilot.
3.
Adjust scanner sighting so that ignition spark and pilot flame are not detected. Test should be
conducted with maximum pilot flame and with both minimum and maximum airflow.
4.
Start main burner.
5.
Adjust scanner sighting to detect main burner flame. When sighting is correct (see above), the
flame relay should energize and the internal LED should be indicating Flame Signal (see table
3).
LED LOCATION
VIEWING LENS
CAUTION: Ensure scanner does not respond to the ignition spark.
CAUTION: Minimum pilot is the minimum flame required to satisfactorily ignite the main
burner. Be sure to test for reliable signals under maximum airflow conditions when the
pilot may not be detected outside the line of sight. If this occurs, resighting is required.
