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PILOT FLAME CHARACTERISTICS
INTERMITTENT PILOT
Correct Pilot Flame Pattern
PILOT
SENSOR
IGNITOR
Figure 17
Incorrect Pilot Flame Pattern
PILOT
SENSOR
IGNITOR
Figure 18
If pilot flame pattern is incorrect, as shown in Figure 18:
• See Troubleshooting, page 27-29.
Cleaning and Pilot Maintenance
Oxygen Depletion Sensor Pilot
When the pilot has a large yellow tip flame, clean the Oxygen
Depletion Sensor as follows:
1. Clean the ODS pilot by loosening nut B from the pilot tubing.
When this procedure is required, grasp nut A with an open end
wrench.
2. Blow air pressure through the holes indicated by the arrows.
This will blow out foreign materials such as dust, lint and spider
webs. Tighten nut B also by grasping nut A.
A
B
VFP(32,36)BP(30,31) Millivolt Pilot
Figure 19
B
A
VFP(32,36)BP(20,21)
Hydraulic Thermostat Pilot
Figure 20
A
B
VFP(32,36)BP(70,71)
Intermittant Pilot
Figure 21
Warning:
Never use needles, wires, or similar cylindrical objects to
clean the pilot to avoid damaging the calibrated ruby that
controls the gas flow.