Fireye D30 Series, Manual

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Keeping the Scanner Cool
The Firetron Scanner (Temperature limit 125F) should never get too hot to grasp comfortable in the
hand. Keep the scanner cool by one or more of the following methods.
1.
Use 6” to 8” length of pipe between scanner and hot furnace front plate.
2.
Use insulating nipple (Part No. 35-69) on the end of the iron pipe.
3. Force air into sighting tube.
4.
Make sure sighting tube does not extend more than halfway into refractory wall.
5. Use Fireye sealing union (part #60-801) when using method 3 above.
INSTALLATION — 69ND1 FLAME ROD
The 69ND1 flame rod proves a gas pilot flame and/or main gas flame. It is a “spark plug” type unit
consisting of 1/2" NPT mount, a KANTHAL flame rod, a glazed porcelain insulating rod holder and
a spark plug connector for making electrical connection. The 69ND1 is available in 12", 18" or 24"
lengths. The flame rod may be located to monitor only the gas pilot flame or both the gas pilot and
main gas flames. It is mounted on a 1/2" NPT coupling.
1. Keep flame rod as short as possible.
2. Keep flame rod at least 1/2" from any refractory.
3.
Flame rod should enter the pilot flame from the side to safely prove an adequate pilot flame
under all draft conditions.
4.
If the flame is non luminous (air and gas mixed before burning), the electrode tip should extend
at least 1/2" into the flame, but not more than half way through.
5.
If the flame is partly luminous, the electrode tip should extend only to the edge of the flame. It is
not necessary to maintain absolutely uninterrupted contact with the flame.
6.
It is preferable to angle the rod downward to minimize the effect of sagging and to prevent it
from coming in contact with any object.
7.
An adequate grounding surface for the flame must be provided. The grounding surface in actual
contact with the flame must be at least four times greater than the area of the portion of the flame
rod in contact with the flame. It is essential to adjust the flame rod and ground area ratio to pro-
vide a maximum test meter reading.
Note: Interference from the ignition spark can alter the true test-meter reading by adding to or sub-
tracting from it. This trend sometimes may be reversed by interchanging the primary wires (line volt-
age) to the ignition transformer, and may be made ineffective by the addition of grounded shielding
between the flame rod and ignition spark.
8. Proven types of flame grounding adapters as shown below may be used to provide adequate
grounding surface. High temperature stainless steel should be used to minimize the effect of
metal oxidation. This assembly may be welded directly over the pilot or main burner nozzle.
WRONG POSITION
OF ROD
INADEQUATE FLAME
PILOT BURNER
CORRECT POSITION OF PILOT FLAME
CORRECT
POSITION
OF ROD
BOMB FIN
GROUNDING ASSEMBLY
THREADED ROD
ASSEMBLY