Program Stop Function; Forced Intermittent Operation (<24 Hours); Low-Fire Shutdown - Siemens LMV37.4 Series Basic Documentation

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7.5.3.7.

Program stop function

To simplify the burner settings in connection with commissioning and service work, the
program sequence of the LMV37.4... can be stopped at the following positions:
1) Air damper in prepurge position
2) Ignition position
3) Interval 1
4) Interval 2
The program stops are integrated in the setting sequence when the plant is
commissioned (refer to chapter Air-fuel ratio curves – settings and commissioning).
After the initial settings, program stops can be activated on the parameter level.
No. Parameter
Program stop
0 = deactivated
1 = PrePurgP (Ph24)
208
2 = IgnitPos (Ph36)
3 = Interv1 (Ph44)
4 = Interv2 (Ph52)
The program stop function is maintained until manually deactivated. If the system halts
at one of the program stops, a message appears on the display of the AZL2...
P
V h min s %
Example: c:204 alternating with d:24 corresponds to a program stop in the prepurge
position.
Figure 27: Message in the case of program stop
7.5.3.8. Forced intermittent operation (<24 hours)
When forced intermittent operation is activated, the unit shuts down for a moment
after 23 hours and 45 min of uninterrupted operation, followed by an automatic restart.
Forced intermittent operation is a standard feature.
No. Parameter
Gas. Forced intermittent operation
239 0 = deactivated
1 = activated
Oil: Forced intermittent operation
279 0 = deactivated
1 = activated
7.5.3.9.

Low-fire shutdown

To prevent the boiler from being shut down under full or nearly full load conditions,
electronic air-fuel ratio control can run the burner to the low-fire position first when there
is no more request for heat (refer to chapter End of operating position).
Basic documentation LMV37.4...
7 Basic unit
24
36
44
52
P
V h min s %
CC1P7546en
20.09.2013