Condenser air conditioner type split external air temperature conditions

The equipment of the residential line was developed and tested by the manufacturers according to standard AHRI210, and the values ​​presented in the capacity labels (Capacity, current and electrical power) refer to an external temperature condition of 35ºC (TBS) and relative humidity of 40 % (TBU of 23.9 ° C). as the external conditions vary, the values ​​of capacity, current and electric power vary as well.
With the system working on Cooling, the higher the external temperature,
less the amount of heat the equipment can take out of the environment (in
Btu / h); as the pressure increases, the mechanical work of the compressor increases and thus the current increases, as well as the electrical power, so the equipment consumes more energy. There is therefore an external temperature limit for the equipment to work with minimum performance and without compromising its mechanical functioning.
With the system running in reverse cycle, or heating, with the change of function of its heat exchangers, it is necessary to withdraw heat from the external environment, but with low temperatures, it reduces the heat exchange and increases the possibility of returning liquid to the compressor , so there is the thawing logic.
However, if the external temperature is below the recommended temperature, the amount of defrost cycles increases, causing discomfort to the user. Therefore there is an external temperature limit for the equipment to work well.