Chapter 6 — Adjustment Procedures
6-12 Part No. 750-184
periods with intervening purge periods than to risk
prolonged fuel introduction. If the pilot does not light
after several attempts, check all components of the pilot
system.
5. When the pilot flame is established, and with the Pilot Adjusting
Cock wide open, remove the Flame Detector from the burner
plate. The pilot flame can then be observed through this open-
ing.
Wear a protective shield or suitable glasses and keep eyes sufficiently
away from the sight tube opening to avoid serious personal injury or
death. Never remove the flame detector while the main burner is
firing. Failure to follow these instructions could result in serious
personal injury or death.
When checking the pilot flame, be aware the electrode is energized.
Failure to follow these instructions could result in serious personal
injury.
6. To make the final adjustment, slowly close the Gas Pilot Adjust-
ing Cock until the flame can no longer be seen through the sight
tube. Then slowly open the cock until a flame providing full sight
tube coverage is observed.
The adjustment must be accomplished within the time limit of the
safety switch or approximately 30 seconds after the detector is
removed. If the control shuts down, manually reset it. Replace the
detector and repeat the process from step 5.
7. When a suitable flame as indicated in paragraph 6 is obtained,
replace the detector. Observe the reading on the micro-ammeter.
The reading should be between 2-1/4 and 5 microamps when
using a lead sulfide detector and a standard amplifier. See the
flame signal table in the manufacturer's bulletin for values of
other combinations.
The flame signal indicated on the annunciator type relay should not
be less than 10 Vdc, and may be as high as 20 Vdc or greater.
The reading must be steady. If the reading fluctuates, recheck the
adjustment. Be sure that the flame detector is properly seated and
that the lens is clean.
8. Return the test switch to the RUN position.
9. If main flame has not been previously established, proceed to do
so in accordance with instructions elsewhere in the manual.
10. The reading of the main flame signal should also be checked.
Observe the flame signal for pilot alone, pilot and main burner
flame together and the main burner flame at high, low, and
intermediate firing rate positions. Readings should be steady and
in the range indicated in paragraph 7. If there are any devia-
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