What negative impacts can occur when a distribution system is located outside of the thermal envelope?

When a distribution system is located outside of the thermal envelope, it can lead to several significant negative impacts, which is why the second choice correctly identifies the situation. The thermal envelope refers to the boundary that separates conditioned space from unconditioned space. When ductwork or distribution systems are placed outside of this envelope, they can become exposed to extreme temperatures, leading to several issues.

Firstly, the HVAC system has to work harder to maintain desired indoor temperatures. Since the ducts are subjected to outdoor conditions, any heated or cooled air traveling through them may lose its thermal energy before reaching the intended living spaces. This inefficiency results in increased energy consumption and higher utility bills.

Additionally, air traveling through longer ducts due to the placement outside the thermal envelope can lead to more significant pressure losses and the potential for more leaks. Duct leakage becomes more pronounced because conditioned air escapes into unconditioned spaces, further exacerbating the issues of efficiency and comfort.

Ultimately, these factors lead to discomfort in the indoor environment, where temperatures may fluctuate more wildly, affecting the overall comfort of occupants. This impacts overall indoor air quality as well, since the system struggles to adequately filter and manage air in less than optimal conditions.

In summary, having a distribution system outside of the thermal