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ACCESSORIES
3: VENTILATION CONTROL
Fan management with the basic and upgraded thermostats depends on the selected operating mode (cool, heat,
heating elements):
- Fan speed:
If the fans are activated, their speed may be:
• Manually selected by the user;
• Automatically selected if the fan switch is set to auto mode (upgraded thermostat only).
- Fan thermostat action:
The fan will activate and de-activate as described on page 31.
- Valve thermostat action:
If the valve thermostat action is enabled, the fan will be automatically set for continuous operation in cool mode
(fans permamently on), while in heat mode, the fan is timed as the probe installed prior to the valve is no longer
able to control the cold air inlet :
• Fan ON 180 seconds after the valve opening command;
• Fan OFF 180 seconds after valve closing command.
The hot start function is always activated (in heat mode) for water temperatures of below 39°C
Automatic ventilation:
The automatic fan speed is regulated according to the difference between the ambient temperature and the value
set by means of the setpoint.
This difference depends on the hysteresis set in the regulator, which is:
• 0.6°C for wall-mounted control units;
• 1°C for controls units mounted on the machine.
The figure below gives the difference values of control units mounted on the machine. The difference values should
be replaced in the following way to adapt the graphs to the wall-mounted model:
- Cool mode: values +1, +2, +3, become +0.6, +1.2, +1.8;
- Heat mode: values -1, -2, -3, become -0.6, -1.2, -1.8.
Graph showing automatic fan management for thermostats on the machine (1°C hysteresis)
Note: the set-point shown in the x-axis of the graphs refers to the value set by the user on the potentiometer.
Fan speed
Ambnient
temp.
Cool mode
Heat mode
Fan speed
Ambnient
temp.