To prevent a system from operating under different air pressure zones, where must combustion air and vent pipes be located?

The correct choice indicates that combustion air and vent pipes must be located near the same area to prevent the system from operating under different air pressure zones. When combustion air and vent pipes are situated close to each other, they can maintain consistent pressure levels, which is crucial for the safe and efficient operation of combustion systems.

If these components are not in proximity, variations in air pressure between different zones can create imbalances that may lead to a situation where the combustion process is either starved of sufficient air or overwhelmed with excess, causing safety hazards such as incomplete combustion or the potential for backdrafts.

This positioning also facilitates the proper mixing of air with fuel and enhances the efficiency of the combustion process, ultimately contributing to better overall system performance.

In contrast, placing the pipes in separate areas or at varying elevations could create discrepancies in pressure that adversely affects combustion efficiency and safety. Confined areas can restrict airflow and lead to similar pressure issues, making the choice of having them near the same area paramount in maintaining system integrity.