12
6.
When proper signal is established, manually close off the main burner fuel supply. When burner
flame becomes unstable or is extinguished, the flame relay should de-energize and the internal
LED should be off.
7.
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.
ACCESSORIES
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.
Table 4:
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 Coupling with Quartz Window
The sealing coupling (60-1199-x) is used whenever a coupling or seal is required for scanner piping.
The size is one inch US standard taper pipe thread (1" NPT). The sealing coupling has a quartz win-
dow to block off the scanner from the furnace pressure and heat. When the sealing coupling 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 coupling collar because damage to the window may result. For best
results, hand tighten coupling collar.
FIGURE
PART
NUMBER
DESCRIPTION
14
53-121
Orifice Kit Contains the Following:
14A
53-121-2
Orifice .062” Diameter
14B
53-121-3
Orifice .078” Diameter
14C
53-121-4
Orifice .093” Diameter
14D
53-121-5
Orifice .109” Diameter
14E
53-121-6
Orifice .125” Diameter
14F
53-121-7
Orifice .187” Diameter
14G
53-121-8
Orifice .250” Diameter
14H
53-121-9
Orifice .375” Diameter
14I
53-121-10
Orifice .50” Diameter
14J
34-181
Orifice Retainer
