True or False: Discharges can be used to cool the pump when no lines are flowing.

The assertion that discharges can be used to cool the pump when no lines are flowing is true. This practice is crucial in the operation of pumps, particularly to prevent overheating. When a pump is running but not actively discharging water through the firefighting lines, it can generate significant heat due to friction and the mechanical operation of the pump components.

By allowing some water to flow through the discharge, it can help maintain a lower operating temperature, thus preventing damage and extending the life of the pump. This technique ensures that there is a consistent flow of water, which aids in dissipating heat effectively.

The other options have specific limitations that do not apply in this context. For instance, the notion that this action is only valid when connected to a water source implies a scenario where resource availability might hinder proper cooling, which isn't typically the case, as discharges can often be utilized directly for cooling. Similarly, the suggestion that this practice is limited to emergency situations overlooks its utility as a standard operating procedure to ensure the reliability and efficiency of the equipment in all scenarios.