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PILOT FLAME CHARACTERISTICS
The correct pilot flame
(Figure 11)
will be blue, extending past
the thermocouple. The flame will surround the thermocouple just
below the tip.
Natural Gas pilots require adjusting when the inlet gas pressure
is above 5” w.c. (1.245kPa). Remove the pilot cover screw on the
control valve
(Figure 3),
and turn the adjustment screw clockwise
to reduce flame. Replace pilot cover screw to eliminate gas leak
-
ing at that control valve opening.
Propane Gas will not require adjustment.
After use, cleaning may be required for the proper flame.
IP-Model Pilot
This heater is using a Honeywell “Smart Valve” system for intermit-
tent pilot ignition.
On a call for heat, this control turns on a 24 volt mini hot surface
ignitor which lights a pilot that in turn lights the main burner. The
gas valve used in this system is a step opening which opens at a
lower pressure for ignition and then steps to a full inlet pressure
of 4” W.C. pressure on Natural Gas and 10” W.C. pressure on
Propane Gas.
Pilot Flame Adjustment
The pilot flame should envelop 3/8 to 1/2 inch (10 to 13mm) of the
tip of the flame rod.
See Figure 11.
To adjust:
1. Remove the pilot adjustment cover screw.
2. Turn the inner adjustment screw clockwise
to de-
crease or counterclockwise
to increase pilot
flame. Pilot adjustment is shipped at full flow rate. Turn the
inner adjustment screw clockwise
if the inlet pres-
sure is too high.
3. Replace the cover screw after the adjustment to prevent gas
leakage.
THERMOCOUPLE
BURNER
SPARK
ELECTRODE
PILOT
STANDING PILOT
THERMOCOUPLE
PILOT SHIELD
SPARK
ELECTRODE
PILOT LOCATION END VIEW
STANDING PILOT SHOWN
3/8” TO 1/2”
PILOT FLAME
GROUND
ELECTRODE
BURNER
PILOT
HOT SURFACE
IGNITOR
FLAME
ROD
IP-MODEL PILOT
Figure 11
