Siemens LMV37.400A2 - Program Stop Function; Forced Intermittent Operation

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Building Technologies Basic documentation LMV37.4... CC1P7546en
HVAC Products 6 Basic unit 01.12.2009
6.5.3.7. 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 24
2) Ignition position 36
3) Interval 1 44
4) Interval 2 52
The program stops are integrated in the setting sequence when the plant is commis-
sioned (refer to chapter Air-fuel ratio control settings).
After the initial settings, program stops can be activated on the parameter level.
No. Parameter
208
Program stop
0 = deactivated
1 = PrePurgP (Ph24)
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
Vh
mi n
s%
Bild 160/0807
P
Vh
mi n
s%
Bild 159/0807
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
6.5.3.8. 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.
Forced intermittent operation is a standard feature.
No. Parameter
239
Gas. Forced intermittent operation
0 = deactivated
1 = activated
279
Oil: Forced intermittent operation
0 = deactivated
1 = activated
6.5.3.9. Low-fire shutdown
To prevent the boiler from being shut down under full or nearly full output conditions, elec-
tronic air-fuel ratio control can run the burner to the low-fire position first, when there is
no more heat request (refer to section End of running position).