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SELECTION OF APPROPRIATE FLAME DETECTOR MODEL 1007
Infrared detectors can be used with almost any single burner application although some difficulty
may be encountered with small gas pilots which have a limited infrared output. The infrared radia-
tion passes readily through normal combustion products and dirty surfaces which makes them very
reliable in single burner applications. When a single scanner is to be used for detecting both pilot and
main flame, the field of view of the scanner must be aimed at the intersection of the pilot and the
main flame. This is to insure that a satisfactory signal from the scanner indicates that there is a flame
at a point which will be sure to ignite the main flame.
Most flames produce sufficient UV for an ultraviolet detector. Even those flames completely invisi-
ble to the eye are easily seen with a UV detector. Since the combustion products of all flames are
opaque in the UV region, this detector is also suited to multiple burner installations. The ultraviolet
detector is ideally suited to all gas burners or combination gas-oil burners.
The area to scan with an ultra-violet detector is within the first 1/3 length of the flame since this is the
major source of UV and also since the combustion products of the flame are opaque in the ultra-vio-
let region.
PROPER FLAME SIGHTING FOR UV SCANNER
The field of view should be area A. Do not try to scan area X at the outer fringes of the flame. The
field of view should include the intersection of the pilot and the main flame so that a signal from the
scanner will insure that the pilot is in the proper position to ignite the main flame.
Since the radiated energy from an electric spark ignitor is very rich in the UV region, the field of
view should be aimed so that it does not see an electric spark ignitor nor any reflector that is close to
the spark.
INFRARED
DETECTOR
ULTRA-VIOLET
SELF-CHECK DETECTOR
ULTRA-VIOLET DETECTOR
Oil Firing
X
X
X
Gas Firing
X
X
X
Strong Refectory
X
X
Continuous Firing
X
X
Intermittent Firing
X
X
X
PRIMARY
COMBUSTION
ZONE
AIR REGISTER
BLADES
SCANNER
LINE OF
SIGHT
BURNER
THROAT
FLAME
ENVELOPE
SINGLE BURNER SCANNER SIGHTING
BURNER
CENTER LINE
BASE
X
A
