Flame proof disagrees with what the technician sees
An oil burner motor and igniter start, and a flame can be seen through the intended inspection point. The primary control nevertheless stops the sequence because its flame-proof requirement is not met. The technician finds that the cad-cell holder was disturbed during cleaning and the sensing surface has a deposit on it. The control’s exact model instructions provide the correct diagnostic method and acceptable operating signal. The customer suggests connecting the sensing wires together permanently so the burner will keep running. The equipment is isolated for inspection, and no temporary diagnostic arrangement is being left in service. The detector mounting can be inspected without changing the approved control arrangement.
1. What should the technician assess?
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Verify the detector’s specified view, cleanliness, wiring and actual signal using the control-specific method, together with the combustion condition. A visible flame to a person does not establish that the optical detector provides valid proof to the primary.
2. Why must the customer’s proposed permanent connection be rejected?
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It would simulate or defeat the protective sensing function rather than repair the cause. Restore the correct detector arrangement, verify valid flame proof and confirm the affected complete operating sequence before accepting normal service.