There are several reasons why a pool should be drained. Most governing bodies state that a pool should be drained every year to make sure water is safe for everyone to use. I will touch on a few of the common reason why a pool should be drained in a moment.
Simply put no. My pool gets lite usage by my immediate family only. I usually drain my pool every two to three years. What dictates my decision to drain is when the TDS (Total Dissolved Solids) are too high or the Cyanuric Acid level is too high.
High TDS, high Calcium Hardness or high Cyanuric Acid. This is the most common reason for draining pools in the great state of Arizona. Typically the supply water is around 250ppm to 500ppm for calcium hardness which is a bit on the high side. This means we are immediately fighting a loosing battle right from the git-go.
When any of these numbers are high the direct result is increased chemical usage. Adding more chemicals into pool water to compensate results in adding more fuel to the fire. At this point it is recommended to drain the pool or spa to ensure every ones safety.
Several repairs require an empty pool as well as a chlorine bath or and acid wash. This being said, there is no alternative... the pool must be empty.
In some cases draining the water is cheaper and healthier then adding a lot of additional harsh chemicals to treat the green water.
This is the number one reason for spas (spas should be drained twice a year). As humans swim we are excreting body oils, dead skin and other things into the water. This stuff is known as Undissolved Solids (UDS) some UDS gets filtered out but some is too small to get trapped in the filter and remain suspended in the water. For proper sanitation heavily used or small water bodies need to be drained more often.
When it is decided that the water needs to be drained your technician will perform the following steps: