Viessmann P10 Installation And Service Instructions Manual page 18

Maintenance
Replacing the circulation pump
LED on the HE circulation pump
LED
Illuminates green
Flashes green in short in-
tervals.
Fault indications
Flashes red and green
■
alternately.
Flashes red
■
LED off
■
18
(cont.)
Meaning
Circulation pump in opera-
tion
Circulation pump in stand-
by
Circulation pump is ready
for operation but not run-
ning.
Note
The circulation pump
starts automatically after
the cause of the fault has
been removed.
Circulation pump switched
off (blocked)
—
Cause
—
—
Undervoltage (< 160 V~)
■
Overvoltage (> 253 V~)
■
Motor temperature too
high
Circulation pump does not
start automatically.
No operating voltage
LED faulty
PCB faulty
Remedy
—
—
Check the power supply:
195 V~ < U < 253 V~
Check ambient and heat
transfer medium tempera-
tures.
Replace the circulation
pump: See page 16.
Check connecting cable.
Check whether the circula-
tion pump is running.
Replace the circulation
pump: See page 16.