Makes no difference with capillary or EEV controlled units with most splits. Cooling mode requires the expansion to occur at the outdoor unit first before entering the indoor unit. There are no expansion valves at the indoor units unless your dealing with VRV/VRF systems or specialised large commercial units.
The reason for this is that the refrigerant can be pushed greater distances with a smaller displacement compressor at the trade off with fixed maximum pipe run lengths depending on unit model size. By creating a pressure drop at the outdoor unit,you have a greater potential to push refrigerant further where as normal subcooled liquid lines run at equal high side pressure and need greater pumping effect.
This is why the liquid line leaving the outdoor unit is not a true liquid line in cooling mode. It is realistically an expanded liquid line and part of the low side evaporator circuit as soon as it leaves the outdoor unit. This is why it needs to be insulated, otherwise it might flash the gas and yes take it from me that latent pipe pair coil rubbish is not good enough.
Keep these pipes out of direct sunlight, but as you go longer in pipe run you will lose the specified unit capacity due to pressure drop. There is NOTHING you can do about that.
The good news is that in heating , the liquid line is a true liquid line and it suffers much lesser losses in capacity for distance.
Now if your going to run a domestic type split the full distance of installation lengh. Ask yourself this very important question,
"should I upsize?"
The standard capacity distance is based on 7.5 metre piping run, with cooling mode. The bigger the capacity the unit is the greater the losses on cooling mode over a longer piping distance. Check the engineering data for this info from your manufacturer of brand air-conditioner
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