6
INSTALLATION
CAUTION: Due to the micro-processor based design of the 45FS1/45UVFS1 scanner, the
heat insulating nipple (P/N 35-127-1 or 35-127-3) must be used to insulate the scanner from
ground and to reduce conducted energy and noise. Failure to do so could result in erratic
operation of the scanner.
The 45FS1/45UVFS1 flame signature scanners determine the presence or absence of flame by moni-
toring the frequency spectrum of the AC signal of the flame to determine the type of flame being
sensed. The scanner should initially be mounted so that the primary combustion zone is within the
scanner’s line of sight.
WARNING: An acceptable scanner location must ensure the following:
1.
Reliable main flame and/or ignitor flame detection at all air flow and furnace loads
(ranges of fuel firing).
2.
Rejection of the ignitor flame if too short or in the wrong position to ignite the main
flame reliably, thus prohibiting the delivery of fuel to the burner.
The location and sighting instructions listed above and in the following section are rough guidelines
for the location of the scanner. The 45FS1/45UVFS1 scanner also provides feed- back via its LED
display to assist in the adjustment and proper alignment of the flame scanner. Refer to the setpoint
“AIM” under Setpoints Menu.
INSTALLATION PROCEDURE
WARNING: Protective filtered lenses should be worn when viewing flame. Infrared and
ultraviolet energy from the flame can be damaging to the eyes.
1.
The best results are obtained when the scanner is aimed so that the scanner’s line of sight inter-
sects the burner center at a slight angle (e.g. 5 degrees) and sees a maximum of the primary com-
bustion zone, as shown in Figure 4. If only one scanner is used per burner, the line of sight should
also intersect the igniting flame.
2.
For installations where separate scanners are used to monitor main and ignitor flames, the main
flame scanner should be sighted so it does not detect the ignitor flame.
3.
The scanner should have an unrestricted view of flame as far as possible. Physical obstructions
such as air register blades, interfering vanes, or other hardware should be cut away or notched so
they do not fall within the scanner’s line of sight as shown in Figures 4 and 6.
Note: Always check with the burner manufacturer before you trim the register blades.
FIGURE 4.
SINGLE BURNER SCANNER SIGHTING
4.
Consideration must be given to burner secondary air rotation (some burners have clockwise air
rotation and others have counterclockwise). If combustion air enters the furnace with a rotational
movement of sufficient velocity to deflect the ignitor flame in the direction of rotation, position
the scanner 10 to 30 degrees downstream of the ignitor as shown in Figure 5 and close to the
periphery of the burner throat (See Figure 4).
PRIMARY
COMBUSTION
ZONE
AIR REGISTER
BLADES
SCANNER
LINE OF
SIGHT
BURNER
THROAT
FLAME
ENVELOPE
BURNER
CENTER LINE
BASE
