Specifications

12
®
Start an adjacent burner and vary its firing rate under normal airflow conditions. Make certain that
the main flame scanner on the burner not in service does not respond to adjacent burner flame.
Readjust sighting if necessary.
Swivel Mount
The scanner swivel mount P/N 60-1664-4 (BSP) or 60-1664-3 (NPT) is used to adjust the scanner
sighting angle after the scanner has been installed. The swivel mount is used as indicated the figures
in this document.
Orifices
The Orifice restricts the field of view (target area), reduces air flow, maintains air flow, maintain air
block, and increases discrimination between flame and background radiation. The orifice is secured
within the ball of a swivel mount with an orifice retainer or the orifice can be placed within a one
inch union (not provided).
The scanner should ideally sight a target area of 4 to 25 square inches (25-150 cm
2
) of the flame
front. The flame front is a plane within the combustion space separating the region of unburned fuel
from the burning fuel.
Note: There is an inverse relationship between discrimination and sensitivity.
Heat Insulating Nipple
The heat insulating nipple P/N 35-127-3 (BSP) or 35-127-1 (NPT) prevents heat transfer from the
hot sight pipe to the scanner head.
Sealing Union with Quartz Window
The sealing union (60-1199) is used whenever a union or seal is required for scanner piping. The size
is one inch US standard taper pipe thread (1" NPT). The sealing union has a quartz window to block
off the scanner from the furnace pressure and heat. When the sealing union is used, the 1" tee/wye is
used for the purge air inlet. Be sure the quartz window is properly seated to seal off the scanner. Do
not over-tighten union collar because damage to the window may result. For best results, hand
tighten union collar.
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.