Viessmann Vitodens 300 Service Instructions Manual page 37

Further details regarding the individual steps
Scanning and resetting the "Maintenance" display
The red fault indicator flashes when the limits set via coding address 21 and 23
have been reached. As regards the operating interface display:
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For constant temperature control units, the hours run (subject to setting) or
the given time interval and the clock symbol flashes.
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For weather-compensated control units "Maintenance" flashes.
Note
Set code 24:1 and then code 24:0, if maintenance is implemented before main-
tenance is displayed; the set maintenance parameters for hours run and interval
are then reset to 0.
1. Press c.
Maintenance scan is activated.
2. Scan maintenance messages
with a or b.
3. Press d, for weather-compen-
sated control units also confirm the
display "Acknowledge: Yes"
with d.
"Maintenance" is cancelled from
the display and the red fault indica-
tor continues to flash.
Note
An acknowledged maintenance
message can be redisplayed by
pressing d (approx. 3 seconds).
Initial start-up, inspection, maintenance
(cont.)
After maintenance has been carried
out
1. Reset code 24:1 to 24:0.
The red fault indicator is extin-
guished.
Note
If coding address 24 is not reset, a
new "Maintenance" message will
be displayed on Monday at
07:00 h.
2. If required:
Press c.
&
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Reset burner hours run, burner
starts and consumption (see
page 70).
Press c.
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