Additional Controls; Emergency Operation - AERMEC AER503IR Manuel D'utilisation Et D'installation

ADDITIONAL CONTROLS

EMERGENCY OPERATION

The following two fault situations are
envisaged:
No Water Probe. In this case, the thermostat
operates as follows:
• Ventilation is always active
• The season change is made on the
basis of the difference between the setting
made and the actual ambient temperature. If
the ambient temperature exceeds an interval
equal to the dead band, Heating Mode passes
to Cooling Mode; If the ambient temperature
drops below an interval equal to the dead
band, Cooling Mode passes to Heating Mode.
In this case, the activation/deactivation of the
heater depends not on the water temperature
but on the mere thermostat operation
request.
No ambient probe (2 pipes)
In this case, the thermostat behaves as
follows:
◆ Selector in OFF - Aux position
• The valve is closed
• The fan is off
◆ Selector in AUTO, V1, V2, V3 position:
• The valve is always open.
• Operating season always hot.
• Ventilation follows On-Off cycles.
The length of the ON cycle is proportional to
the selected setpoint (manual control of the
power supplied by the terminal). The total
duration of the ON-OFF cycle is 5'20".
No ambient probe (4 pipes)
In this case, the thermostat behaves as
follows:
◆ Selector in OFF - AUX position
• The valves are open
• The fan is off
◆ Selector in AUTO, V1, V2, V3 position:
• The operating season is decided
by the setup position, with very low setpoints
the system switches to cooling mode and,
vice versa, with high setpoints the system
switches to heating mode.
In this case, ventilation follows ON-OFF
cycles but the ON phase is increased from
the central position upwards. This means
maximum ventilation can be requested with
the selector on the minimum position for
cooling mode, and with the selector on the
maximum position for heating mode. The
total length of the ON-OFF cycle remains
5'20'' . The following table shows examples
of the duration of the various ON/OFF cycles
according to the position of the temperature
selector:
ON cycle OFF cycle
Setpoint
duration duration
Min 5'20" 0
Central 0 5'20"
Max 5'20" 0
No ambient probe (2 pipes for cooling +
Heater for heating)
In this case, the thermostat behaves as
follows:
◆ Selector in OFF position
• The valves are open
• The fan is off
◆ Selector in AUTO, V1, V2, V3, AUX position:
◆ The operating season is decided by the
setup position, with very low setpoints the
system switches to cooling mode and, vice
versa, with high setpoints the system switches
to heating mode.
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