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8.1 Safety thermostat in electrical heater
(optional equipment)
If an error occurs on an electrical heater, the safety
thermostat will disconnect.
The heater is equipped with a fire thermostat that
automatically cuts off the power supply, if the
temperature exceeds 80 °C. If the temperature decreases,
the heater automatically re-engages.
As an additional security there is a built-in thermal cut-
out, which disengages if the temperature exceeds 110 °C.
Re-engaging must be done manually.
Does not apply to PTC electrical heaters.
8.2 The system is not running
Unit stopped
Possible error:
• Fuse in main board has blown, no power to unit.
• One of the fuses on the circuit board of the unit isblown.
• Loose wire, no power to unit.
• Loose wire between unit and control panel.
• Faulty or incorrectly set week program.
• Filter timer has switched the system off.
Condensed water is leaking from the unit
Possible error:
Condensation outlet blocked by dirt.
The condensation outlet is not adequately protected
against freezing at low outdoor temperatures.
8.3 Air faults
No supply air:
Possible error:
• Faulty supply air fan
• Clogged supply air fi lter
• Clogged fresh air grill due to dirt and leaves during the
fall and snow and ice during the winter.
• Fuse on the circuit board is blown.
• The unit is in defrost mode (supply air fan stops)
• Incorrect value set in User menu item 2.
No extract air:
Possible error:
• Faulty extract air fan
• Clogged extract air fi lter.
• Fuse on the circuit board is blown
Cold supply air:
Possible error:
• Clogged heat changer.
• Faulty extract air fan.
• Clogged extract air filter.
• Electrical reheater is disconnected at the over heating
thermostat (only units with electrical reheater
installed).
• Air in the heating pipes, faulty thermostat / motorvalve,
incorrect setting of control panel.
8. TROUBLESHOOTING
