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Operation and maintenance instructions – v2.8.8 & 2.7.3
5.2 TEMPERATURE CONTROL
5.3 FREE COOLING (RX
AND
PX)
There are several options available on GLOBAL units to ensure a comfortable temperature.
The options are controlled either via supply or extract air temperature.
The free cooling function uses the lower temperature of the outside air to cool the building.
Free cooling is realized by means of the integrated 100% modulating bypass of the heat exchanger (PX) or the stepless
motor control of the rotary heat exchanger (RX). The optional output O.R.4 on the SAT3 relay indicates the position of
the bypass. The contact will open if the bypass is fully closed, or close if the bypass is fully or partially open.
The bypass (PX) or the rotary heat exchanger (RX) can be configured as on/off or modulating. This is configured
in ADVANCED SETUP. In modulating mode, the temperature is configured in the base setup and the position of
the bypass/stepless motor will modulate in order to maintain the setpoint. The free cooling function is activated
automatically. An on/off bypass / stepless motor operates according to the logic below:
Free cooling STARTS if the following conditions are TRUE :
These Settings can be configured in ADVANCED SETUP
Free cooling STOPS if one of the following conditions is TRUE :
Extract Air Temperature
The default temperature control can be changed to Extract temperature control via the advanced setup.
The extract air temperature is measured on sensor T2. Extract air control involves keeping a constant temperature in
the extract air duct (premises), by controlling the supply air temperature. This provides a uniform temperature in the
premises regardless of the load. The internal sensor T2 can be replaced with the optional external room temperature
sensor (CID370042).
Temperature sensor positioning :
•
The outdoor temperature (sensor T1) is lower
than the extract air temperature (sensor T2)
•
The outdoor temperature (sensor T1) is
higher than 15°C.
•
The extract air temperature (sensor T2) is
higher than 22°C.
•
The outdoor temperature (sensor T1) is higher
than the extract air temperature (sensor T2).
•
The outdoor temperature (sensor T1) is
lower than 14°C.
•
The extract air temperature (sensor T2) is
lower than 20°C.
Supply Air Temperature
Supply temperature control is the default setting. This involves keeping a constant supply air temperature without
consideration to the load in the premises. The supply air temperature is measured on sensor T5.
Summary of Contents for GLOBAL LP FW
Page 15: ...15 Operation and maintenance instructions v2 8 8 2 7 3 4 3 INTERNAL WIRING DIAGRAM GLOBAL PX...
Page 17: ...17 Operation and maintenance instructions v2 8 8 2 7 3 4 5 INTERNAL WIRING DIAGRAM GLOBAL LPFW...
Page 59: ......
Page 60: ...We make every breath count Version 27 09 2018 We reserve the right for changes...