In an air-to-air split system heat pump, what is the small diameter interconnecting tubing referred to as?

In an air-to-air split system heat pump, the small diameter interconnecting tubing is referred to as the liquid line because it is specifically designed to transport refrigerant in its liquid state from the indoor evaporator coil to the outdoor condenser unit.

This line plays a crucial role in the heat pump’s operation, allowing the refrigerant to pick up heat from the indoor environment and carry it to the outdoor unit, where it is released. The proper function of the liquid line is essential for efficient heat transfer, as it connects key components of the system and ensures that refrigerant cycles effectively, helping to maintain the desired indoor temperature. Understanding the function of the liquid line is key to troubleshooting and servicing heat pump systems.