Principle Of Functioning - Technibel iSeries Technical Data & Service Manual

6 Principle of functioning

Heating mode
When the unit is in heating mode, the system will regulate the heating capacity delivered to the room to
increase the room air temperature (RAT) to the set point (SPT) and to balance the thermal load of the
room to keep the set point temperature.
The following rules apply to heat mode functioning:
Compressor and fan start when RAT is 1°C or more below the SPT
-
Compressor and fan stop if RAT is 2°C or more above the SPT, or if RAT is 1°C above the SPT for
-
more than 1 hour
During the first 3 minutes of operation:
Compressor and fan run at a fixed speed (2 minutes at low speed and 1 minute at intermediate
-
speed)
EEV is open at a fixed value
-
After the first 3 minutes of operation, compressor and fan speeds are regulated by:
the thermal load calculation
-
the level of protecion of the system
-
During heating mode, 4-way valve is active.
Cooling mode
When the unit is in cooling mode, the system will regulate the cooling capacity delivered to the room to
decrease the room air temperature (RAT) to the set point (SPT) and to balance the thermal load of the
room to keep the set point temperature.
The following rules apply to cool mode functioning:
Compressor and fan start when RAT is 1°C or more above the SPT
-
Compressor and fan stop if RAT is 2°C or more below the SPT, or if RAT is 1°C below the SPT for
-
more than 1 hour
During the first 3 minutes of operation:
Compressor and fan run at a fixed speed (2 minutes at low speed and 1 minute at intermediate
-
speed)
EEV is open at a fixed value
-
After the first 3 minutes of operation, compressor and fan speeds are regulated by:
the thermal load calculation
-
the level of protecion of the system
-
During cooling mode, 4-way valve is deactivated.