Which of the following components are generally exempt from being tested under the Mechanical Code?

Certain components under the Mechanical Code are often exempt from testing requirements to streamline installation and facilitate compliance. In this case, compressors, refrigerant lines, and safety devices are typically considered essential to the mechanical system's operation but may not require exhaustive testing.

Compressors, crucial for HVAC systems, are usually pre-tested by manufacturers for performance and reliability, so additional testing in the field is often unnecessary. Similarly, refrigerant lines are primarily inspected for physical integrity and proper installation rather than operational testing, as these lines are sealed and designed to withstand the pressures of the refrigerant. Safety devices, designed to activate under specific conditions to prevent system failures or hazards, are generally checked for installation and operational status rather than subjected to rigorous testing protocols.

Choosing the option indicating that all these components are exempt highlights an understanding of the code's purpose: ensuring safety and functionality without imposing redundant or excessive burdens on installers or systems that have demonstrated reliability through manufacturing processes.