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7. HEATING UNIT TROUBLE-SHOOTING
HEATING UNIT
CONDITION
MALFUNCTION
PROBABLE CAUSE
REMEDY
The heating unit has shut down,
the red shutdown light no.1 is
ON.
See 4.10 paragraph “Burner
troubleshooting”.
See 4.10 paragraph “Burner
troubleshooting”.
See 4.10 paragraph “Burner
troubleshooting”.
The heating unit has shut down,
the red shutdown light no.2 is ON.
Press no.17 button in order to
reset the unit.
The safety thermostat has shu-
tdown the heating unit
Water is not flowing in the CH
system: the pipes are clogged,
the thermostatic valves are clo-
sed, the system cut-off valves
are closed.
Check the system.
The pump is jammed or faulty.
Check the pump.
The heating unit has shut down,
the red shutdown light no.4 is
flashing.
Restore correct water pressure
in order to resume unit opera-
tion.
Insufficient water pressure in the
CH system
CH system is leaking.
Check the system.
Pressure switch is discon-
nected.
Reconnect it.
Pressure switch is not working:
it is faulty.
Replace it.
The heating unit has shut down,
the red shutdown light no.5 is
flashing.
The unit will automatically resu-
me operation once the problem
is solved.
Flow probe is faulty.
Flow probe is disconnected.
Reconnect it.
Flow probe is faulty.
Replace it.
The heating unit has shut down,
the red shutdown light no.6 is
flashing.
The unit will automatically resu-
me operation once the problem
is solved.
Communication with the remote
control is faulty or there are
connection problems.
The remote control wire is
disconnected from the remote
contacts or from the heating unit
contacts or it is interrupted.
Check the remote control con-
necting wire.
The heating unit has shut down,
the red shutdown light no.7 is
flashing
(B and BV models).
The unit will automatically resu-
me operation once the problem
is solved.
Water tank probe is faulty.
Water tank probe is
disconnected.
Reconnect it.
Water tank probe is faulty.
Replace it.
The red light no.9 is flashing and
the heating unit has not shut
down.
The unit will automatically resu-
me operation once the problem
is solved.
Temperature of water in the
boiler has exceeded 80°C.
Water is not flowing in the CH
system: the pipes are clogged,
the thermostatic valves are clo-
sed, the system cut-off valves
are closed.
Check the system.
The pump is jammed or faulty.
Check the pump.
The heating unit is not operating
in DHW mode.
(B and BV models).
Water flow to tank is not ade-
quate.
The system pressure or flow rate
is not adequate.
Check the DHW system.
Water tank probe is not working. Water tank probe is faulty.
Replace it.