MAXA HWA1-A 0140, Руководство пользователя

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HWA1-A
Air/water chillers with axial fans
16
The free-cooling demand will be activated when the outdoor temperature is lower with
F26 than the intake temperature.
After activation of the free-cooling, it will stop when the outdoor temperature increases above T
intake
- F26 + F27 .
The free-cooling control valve is active when free-cooling demand is active.
14.1.1 Ventilation in freecooling
When the free-cooling control valve is active:
When compressors are active, or if compressors are called, the ventilation starts as described in the condensation control
controller.
If the compressors switch off for satisfied thermoregulation, the ventilation logic switches the control to free-cooling demand with
the following modes:
-
The ventilation is forced at maximum speed (100%) for the first F25 minutes.
-
When the time defined by F25 is terminated, the regulation becomes PI type with band given by b01 , the setpoint is that
of the current plant water regulation.
-
In case of turning back to the zone of compressors thermoregulation call, the ventilation returns under the condensation
control.
14.2 Enablement of domestic hot water production (DHW)
In sanitary mode, the maximum power is employed (like when the thermoregulator is asking always for 100%). However, the
various limitations of the maximum frequency associated with the envelope and the limitation for maximum electrical absorption
are active.
To activate this function, it is necessary to connect to the
ST2E – ST2E terminals (enabled as analog input) a temperature sensor
which should be placed inside the water tank. Once connecting and placing the sensor, then it is necessary to enable the domestic
hot water function.
To enable this function, enter at the parameters PRG
→
PSS
→
PRG
→
(introduce the maintainer password)
→
PRG
→
PAr
→
PRG
→
CnF .
I/O port – Parameter Value Function
H10
0 (default) Deactivated function
1
Active function in heating and cooling mode.
The remote on-off function doesn’t deactiv ate the domestic hot water production (DHW).
2
Active function in heating and cooling mode.
The remote on-off function deactivates the domestic hot water production (DHW)
3
Active function in heating mode.
The remote on-off function doesn’t deactiv ate the domestic hot water production (DHW).
4
Active function in heating mode.
The remote on-off function deactivates the domestic hot water production (DHW)
5
Active function in cooling mode.
The remote on-off function doesn’t deactiv ate the domestic hot water production (DHW).
6
Active function in cooling mode.
The remote on-off function deactivates the domestic hot water production (DHW).
H29 6 Activation of domestic hot water temperature sensor DHW (ST7E terminals)
H90 6 DHW valve command (D05E/D05EN terminals)
If the DHW temperature is below the set point value ( PRG->Set->SAN ), the unit activates the sanitary valve and the compressor
will be placed at the maximum frequency starting the modulation at 1°C before (setpoint-1°C) the set value and it stops at 1°C
after the set value (s1°C). Once achieved the set point value, the valve switches to the stand-by mode and the
compressor works normally.
While shifting from user’s to domestic hot water, the operating sensor changes from “ outlet water temp. sensor ” to “ sanitary
tank temp. sensor ”. While shifting from the winter operating mode to the sanitary operating mode, the compressor does not stop
operation, and will be placed at the maximum established frequency which can be controlled; however, when shifting from the
summer operating mode to the sanitary operating mode, the compressor will stop operation for waiting for the safe period.
The defrost cycle during winter operation mode is always performed on the user side, never on the sanitary water tank.
ON
OFF
Temperatura esterna
Freecooling demand
Temperatura di ripresa
F27
F26