What is the name of the larger diameter interconnecting tubing in a heat pump system?

In a heat pump system, the larger diameter interconnecting tubing is known as the gas line. The gas line is responsible for transporting refrigerant gas between the indoor and outdoor units of the heat pump. This gas line typically carries the low-pressure vapor from the evaporator coil in the indoor unit to the compressor and then out to the outdoor unit where it is condensed back into a liquid.

The key characteristic of the gas line is its larger diameter compared to the liquid line, which is narrower and designed to transport refrigerant in its liquid state. Understanding the function and specifications of the gas line is crucial for effectively diagnosing and servicing heat pump systems, making it an essential component in maintaining proper heat pump operation.