MAXA i-MAX 0466, Manual

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i-MAX
Industrial inverter air/water heat pump with axial fans
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7.5.3 FAN SPEED CONTROL IN HEATING MODE
The fan speed control in heating mode follows the diagram shown below, where:
F10 = Delta cut-off of the fan in cooling/heating mode
F11
= Cut-off hysteresis in cooling/heating mode
F15 = Minimum fan speed in heating mode
F16 = Maximum silent fan speed in heating mode
F17
= Set pressure for the minimum fan speed in heating mode
F18 = Fan speed linear band in heating mode
F19 = maximum fan speed in heating mode
F20
= Set pressure for the maximum fan speed in heating mode
F17+F10 = Set forced fan stop for high evaporating pressure
The fan speed can be controlled via analog/digital outputs or, alternatively, via serial on the same serial of the modulating
compressor. Please see paragraph 11.5 for changing the parameters.
7.6 DEFROSTING CYCLE
The defrost cycle function is available only in heat pump mode and is used to prevent the frost formation on the surface of the
air/air coil. The frost formation on the evaporator, which occurs more frequently at very low ambient temperatures, further the
important decreasing of the thermal efficiency of the unit, it can lead also to the risk of damaging the unit itself. The adjustable
parameter d01 enables the defrost operation (=1 enabled defrosting). Please see paragraph 12.7 for changing the parameters.
7.6.1 FORCED MANUAL DEFROST
If the appliance is in ON in heating mode, you can force manually the defrosting mode by pressing the UP, DOWN, and ENTER
buttons for 3 seconds.
The same thing can be done via serial, sending the modbus 200 register value '-1'. This item will not change the state of the
appliance, but only leads to forced manual defrost.
7.7 COMPRESSOR CRANCKASE HEATER
The crankcase heater operates when the compressor remains off for at least 30 minutes and if the discharge temperature is below
20°C (with hysteresis of 2.0°C). When the compressor restarts, the crankcase heater will stop.
7.8 ANTIFREEZE PROTECTION ELECTRIC HEATERS (WHEN THE “KA” ACCESSORY IS PRESENT)
The electric heaters of water antifreeze, installed on the outer plates’ surfaces of the evaporator, turn on even if the unit is off
(but energized) if the outlet water temperature goes below r02 °C (default is 4°C) in heating mode or below r03 °C (default is 4°C)
in cooling mode and in shut off condition. The same electric heaters are switched off when the temperature measured by the