When installing copper tubing refrigerant lines that require bends, what tool should be used to avoid collapsing the tubing?

Using a lever type tubing bender is the correct choice for installing copper tubing refrigerant lines with bends to prevent collapsing the tubing. This tool is specifically designed to create smooth, even bends in metal tubing without causing kinks or deformation, which is essential for maintaining the integrity of the refrigerant lines. Collapsing could lead to reduced flow, inefficiency, or potential leaks, all of which would compromise the performance of the cooling system.

The lever-type bender operates by providing leverage that controls the bending process, ensuring that the radius of the bend is smooth and that the cross-section of the tubing remains intact. It helps to distribute the stress evenly along the tubing, minimizing the risk of damage during bending.

Other options like pipe cutters, adjustable wrenches, and pliers serve different purposes. Pipe cutters are meant for cleanly cutting tubes but do not assist in bending and could potentially damage the tubing if misused. An adjustable wrench and pliers can grip and tighten or remove fittings, but they lack the precision required for bending without risking damage. Therefore, the lever type tubing bender is the most suitable and effective tool for this specific task.