Auto A/C Terms - Glossary
High Pressure Line(s)

Every A/C system is divided into two sides. The high side is high pressure, high temperature refrigerant while the low side is low(er) pressure and temperature. The high pressure lines are the ones that connect the compressor outlet (or discharge) to the condenser inlet and from the condenser outlet to the receiver drier (if equipped) and expansion valve or orifice tube.

That line, from the condenser outlet is also referred to as the liquid line of the system because it will typically always have liquid refrigerant in it. That’s because the function of the condenser is to condense vapor refrigerant from the compressor to liquid refrigerant, so that it can be returned to the evaporator.