SECTION FOUR – Routine Maintenance and Professional Servicing
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The Air Flow Switch (AFS) is fastened to the Control
Box.
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FF
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The Air Flow Switch senses the pressure differential
across the air orifice to prevent the burner from firing if
there is insufficient air flow. The AFS is factory-set and
is nonadjustable.
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SS
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To replace the AFS:
1. Turn off the pump and all electrical power to the
heater .
2. Disconnect the plastic tubing from the AFS fittings.
3. Disconnect the wires from the AFS.
4. Remove the screws fastening the AFS to the Control
Box.
5. To Replace the AFS, reverse Steps 1 through 4
above.
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