PILOT SYSTEMS
E. Cause: Plugging Cures: 1. Disconnect gas line to mixer. Blow into regulator vent opening, or screw adjusting plug up to open regulator (note original position). 2. Remove test plug from mixer and use opening to check air pressure. It should be 6 to 12 osi. 3. If gas flows, return adjusting plug to original position. Check venturi orifices for fuzz, pipe scale or cuttings. Venturi must be unobstructed. 4. Remove pilot tip and check piloting holes for foreign matter or burrs. 5. Turn on air to the pilot mixer. If the suction on the pilot gas connection is not as great as specified in the pilot bulletin, remove gas piping from mixer and check inlet orifices for scale, chips, or oil.
TROUBLE SHOOTING PILOTS
Symptom: Pilot lights but blows out easily A. Cause: Flame too rich. Check: 1. Low air pressure 2. Dirty venturi in mixer
3. Gas adjustment on venturi mixer open too far. 4. Large capacity tip on small capacity mixer. 5. High suction in combustion area; cross-connect the pilot regulator to the pilot air line.
B. Cause: Fluctuating gas pressure.
Cures: 1. If gas supply pressure fluctuates rapidly due to chattering regulator, the pilot will be unstable. To remedy chattering, remove dirt from the pilot regulator's valve seat. If the seat is damaged, replace the pilot regulator. 2. If chattering persists, substitute a smaller pilot regulator if possible.
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