Air Pressure Switch - Viessmann VITOCROSSAL 200 Service Instructions Manual

Air pressure switch

Air pressure switch
Fan pressure monitoring function (LDW1)
B A
The switching threshold of air pressure
switch 1 (LDW1) is monitored in all fan
ramp-up phases and checked in modu-
lating burner operation. This minimises
pre-purge.
Air pressure switch A triggers a fault
shutdown at the burner control unit under
the following circumstances:
■ If the static pressure check was unsuc-
cessful after approx. 5 minutes
■ If the air pressure is outside the per-
missible range during the pre-purge
phase (tolerance time approx. 5
minutes)
■ If the air pressure switch fails in regular
operation or the air pressure lies out-
side the permissible range
46
The fault shutdown is shown with fault
indicators "F F5" and "F F7" on the
burner control unit display (see
page 48) and can be reset by pressing
reset button B.
Rated Rated
heating heat in-
output put
P Q (H
max max
(50/30 °C) [net cv]
in kW in kW
400
500
620
LDW1 set val-
ue
)
i
in mbar (kPa)
381
474 2 (0.2)↓
593