Why should pliers be avoided when servicing a valve?

Pliers should be avoided when servicing a valve primarily because they can easily damage the valve's finished surface. Valves often have delicate finishes that are put in place to prevent corrosion and ensure proper sealing. When pliers are used, especially in a gripping or twisting motion, they can mar the surface, leading to scratches or dents. Such damage can not only affect the appearance but also compromise the valve's functionality and sealing ability, potentially leading to leaks or failures in the plumbing system.

Using tools specifically designed for plumbing applications, like dedicated valve wrenches, offers better control and minimizes the risk of surface damage. This is crucial in maintaining the integrity of the valve and ensuring that it operates as intended without future issues. The concern raised about the weight of pliers does not impact their suitability for the task at hand, nor do issues related to rust development, which generally pertain to the materials and conditions rather than the act of using pliers directly.