Crown Boiler BWF Series, Инструкция к добавке

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while the Heating Circulator continues to operate. The ignition sequence will restart (from Step 3) when the water tempera-
ture falls to the high limit setting (
HL
) minus the high limit differential (
HdF
).
A call for DHW results in a sequence of operation that is identical to that described above except for omission of the thermal 11)
purge function described in (2).
E. Safety Control Operation
Air Pressure Switch (APS) - The APS proves that the fan is running before allowing the igniton sequence to proceed. Failure of
this switch to close is usually the result of a problem with the vent system, such as a blockage, or a problem witgh the fan. If this
switch must be replaced, it must be replaced with an identical switch or one that is shown in Crown documentation as being a
suitable repelacement for this boiler (see Parts Section of boiler installation manual).
Flame Roll-out Switch (BWF series only) - Automatically interrupts boiler operation when flames or excessive heat are present in
vestibule. The flame roll-out switch is a single use device which must be replaced by an identical switch in order to restore normal
operation. An open flame roll-out switch is usually indicative of a plugged heat exchanger. The cause of the flame roll-out must
be found and corrected by a qualified gas service technician, and the switch replaced with an identical one, before the boiler is
returned to operation.