Product Overview

Housing Material: Cast aluminum

Weight: 7 lbs. (3.2 kg)

Housing Dimensions: See Fig. 1

Purge Air: 4 SCFM (113L/min) at 3/8 inch threaded housing inlet or 4 SCFM at 1 inch wye fitting

in scanner sight pipe. Temperatures near the upper limit of the scanner operating range and/or use

with dirty duels may require up to 15 SCFM (425 L/min.).

Optical Range: 2200 to 2600 angstroms. No response to infrared radiation or visible light.

Optical Field of View: 1 inch per foot (25.4mm/305mm)

Operating Range: 72 inches (1830mm) or less.

INSTALLATION

The best scanner sighting results are obtained when the scanner is aimed so that its line of sight inter-

sects the burner center line at a slight angle, as shown in Figure 2. The area of maximum ultraviolet

radiation is near the base of the flame envelope. When only one scanner is used per burner, the inter-

section should be made so the line of sight or viewing angle can also see the pilot flame. Consider-

ation must be given to burner secondary air rotation (some burners have clockwise air rotation and

others counter-clockwise). Figure 3 illustrates how scanner location is influenced by the pilot posi-

tions and secondary air circulation. Physical obstructions such as air register blades should not fall in

the line of sight of the scanner.

FIGURE 2.

1. AN ACCEPTABLE SCANNER LOCATION MUST ENSURE THE FOLLOWING:

— Reliable pilot flame detection.

— Reliable main flame detection.

— Rejection of pilot flame too short or in the wrong position to ignite the main flame reliably,

thus prohibiting main fuel admission.

NOTE: Reliable signals must be obtained at all air flows and furnace loads (ranges of fuel firing).

PRIMARY

COMBUSTION

AIR REGISTER

BLADES

SCANNER

LINE OF

SIGHT

BURNER

THROAT

FLAME

ENVELOPE

SINGLE BURNER SCANNER SIGHTING

BURNER

CENTER LINE

BASE

ZONE