Protections - Technibel iSeries Technical Data & Service Manual

9 Protections

The unit is equipped with an automatic system of protections. These protections, if active, will limit the
speed of the compressor in order to run the system in a safe operating area.
Protections, when active, reduce the speed of the compressor linearly down to its minimum speed. If the
level of protection is too high, compressor is stopped until no protection will be active.
Overheating on outdoor unit heat exchanger
This protection checks the temperature on the outdoor coil (OCT) to avoid overheating and overpressure
of the heat exchanger.
This protection is active only in cooling or dry mode and starts to limit the compressor speed when OCT
is higher than 55°C.
Overheating on indoor unit heat exchanger
This protection checks the temperature on the indoor coil (ICT) to avoid overheating and overpressure of
the heat exchanger and reduces the high pressure noise inside the indoor unit.
This protection is active only in heating mode and starts to limit the compressor speed when ICT is
higher than 40°C(*).
Notes:
(*) ICT threshold may vary depending on the model of the indoor unit
-
If High Power option is active, protection will start at higher values of ICT, increasing the heating
-
capacity
Freeze-up on indoor unit heat exchanger
This protection checks the temperature on the indoor coil (ICT) to avoid freezing of the indoor unit heat
exchanger.
This protection is active only in cooling or dry mode and starts to limit the compressor speed when ICT
is lower than 8°C.
Furthermore, if the unit is stopped because of this protection, in order to drip away all the condensed
water on the indoor coil, it will not restart until ICT is higher than 8°C.
Overheating on the compressor
This protection checks the compressor's discharge temperature (CDT) to avoid overheating of the
compressor.
This protection is always active and starts to limit the compressor speed when CDT is higher than 90°C.
Overheating on the power electronic
This protection checks the temperature of the electronic power module connected to the heatsink. The
temperature sensor is built into the module, so there is no direct access to it.
This protection is always active and starts to limit the compressor speed when power electronic
temperature is higher than 90°C.