Vents VUT R 400 TN EH EC A17, Руководство пользователя

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The unit is equipped with a built-in automatic control system and a control panel.
The automatic control system has the following functions:
1. Switching the unit on/off.
2. Unit operation mode selection: Automatic mode, Cooling mode, Heating mode, Ventilation mode (with pGD1 panel only).
3. Maintaining a pre-set room temperature by activating/deactivating the rotary heat exchanger and the heat pump. The automatic control system also controls
the 4-way valve while heating or cooling the supply air and the air pre-heater unit operation by means of posistor heaters which engage on a section-by-section
basis. The first section is engaged when the outdoor air temperature drops below -8 °C whereas the second pre-heating section is engaged when the outdoor
temperature drops below -16 °C.
The posistor heater is absent on the VUT R...TN H EC units. If this unit modification is to be used in cold climatic conditions an in-line heater should be built into
the supply duct. The unit has a no-contact for heater control.
4. Maintaining air humidity below a pre-set level.
5. Maintaining the CO
2
content in the air below a pre-set level. The CO
2
sensor is connected to the terminals replacing the humidity sensor. The СО
2
sensor must
be rated 24 VAC and produce a 0-10 VDC measured voltage output signal.
6. Condenser defrosting control in the Heating mode.
7. Automatic reduction of the supply and exhaust ventilation flow rate to obtain the user-defined heating temperature.
8. Blocking cold air supply into the serviced spaces in the Auto or Heating mode by warming up the evaporator.
9. Heat pump protection against excessive pressure by means of air flow bursts.
10. Supply and exhaust fan operation control.
11. Filter contamination control (by the number of operating hours).
12. Unit operation according to a pre-programmed schedule.
13. Heat pump protection against abnormally high or low pressure in the freon line.
14. Control of the electric actuators operating the external air dampers (supply and/or exhaust) and the recirculation actuator.
15. System shutdown on command from the fire alarm board.
AUTOMATIC CONTROL SYSTEM DESIGN AND OPERATION
The automatic control system comprises a Carel controller (PCO5 compakt), an outdoor air temperature sensor, the sensor for the air
temperature downstream of the heat exchanger, a supply air temperature sensor, a sensor for the air temperature in the exhaust duct, an indoor
air temperature sensor, a sensor for the temperature at the heat-transfer units, a high pressure sensor, a low pressure sensor, a compressor
starter, circuit breakers, a magnetic starter, a supply transformer and an automatic compressor shutdown switch. The unit is controlled via
th-Tune or PGD1 remote control panel.
The automatic control system enables safe automatic operation of the unit in the Auto, Cooling, Heating or Ventilation mode. In the Auto
mode the unit maintains the indoor temperature at the pre-set level by automatically switching the 4-way valve to the heating or cooling
mode, by enabling the heat exchanger and the compressor and by sending heating activation signals. While in the Heating and Cooling
modes the automatic control system ensures the operation of the unit actuators in the required mode (heating or cooling only) and controls
their performance. While in the Ventilation mode the unit adjusts the supply and exhaust fan speed, but does not control the air temperature.
The Ventilation mode is appropriate for energy saving and ventilation if the difference between the outdoor and indoor temperatures is
insignificant.
The supply and exhaust fan speed is set for each speed stage as a percentage from the maximum rotation speed.
The temperature is set up by changing the «Setpoint» parameter value.
The fans can be operated according to a daily schedule (up to 6 time ranges).
While in the Heating mode when the heat pump is on the unit periodically enters a defrosting cycle. The Defrosting mode is enabled when
the condenser temperature falls below the value set via the controller menu (defrosting setpoint) at the frequency determined by setting the
«Defrosting duration» parameter.
The Automatic Speed Drop mode can be enabled when the air temperature is low. In this mode the fan speed is adjusted according to the
supply air temperature. The speed is reduced at temperature dropping and is restored to the initial setting provided a sufficient temperature
reserve.
N
L
pGD1 control panel
connector
Neutral bus
in a plastic casing
Bolt-down
terminal (X1)
Electromagnetic
relay (K1, K2, K3)
Electromagnetic
relay (K1, K2, K3)
Condenser (C1)
N
L
pGD1 control panel
connector
pCO5 compact
controller (Z1)
F1 — 3 A fuse
F2 — 1 А fuse
Neutral bus
in a plastic casing
Bolt-down
terminal (X1)
Condenser (C1)
F1 — 3 A fuse
F2 — 1 А fuse
Magnetic starter
(KM1)
Transformer (TR1)
Automatic circuit
breaker (Q1)
pCO5 compact
controller (Z1)
Magnetic starter
(KM1)
Transformer (TR1)
Automatic circuit
breaker (Q1)
Control unit
of VUT R 400 TN EH EC
VUT R 700 TN EH EC / VUT R 900 TN EH EC
control unit
UNIT CONTROL