An elevated reading from the vacuum gauge of a high rate sand filter may indicate what?

An elevated reading from the vacuum gauge of a high rate sand filter typically indicates that the filter is experiencing increased resistance to water flow, which is often caused by the accumulation of dirt and debris trapped within the filter media. When the filter becomes clogged, the water cannot pass through as easily, leading to higher pressure readings on the gauge.

Backwashing the filter serves to reverse the flow of water through the system, dislodging the contaminants and flushing them out of the filter. This process restores proper flow and pressure levels, allowing the filter to function effectively again. Regular backwashing is a crucial part of filter maintenance to ensure optimal water clarity and circulation in the pool.

In this context, cleaning the hair/lint strainer or adjusting pool inlets, while also important maintenance tasks, would not directly address the pressure build-up indicated by an elevated gauge reading, nor would it resolve issues related to the filter's ability to process water effectively. Similarly, the collection of air within the filter does not directly result in an elevated gauge reading, as air typically causes a drop in pressure rather than an increase. Thus, recognizing that the primary action needed to address an elevated reading is to backwash the filter is essential.