One of the questions we get asked most often is, what the purpose of the main drain in my swimming pool?
The Main drain pot at the bottom of your pool provides increased mixing of the water in your pool. Provided it is hooked up on its own dedicated line. The water gets sucked through your drain and goes into your pool pump, then through your pool filter and then back to your pool.
Main drains increase mixing of pool chemicals and keep the temperature of your pool more consistent throughout, from the top right down to the bottom.
History of the Pool Drain
Main drains were first installed on pools over 100 years ago as a way to drain the pool. Pools back then did not use modern sanitation methods and therefore needed to be drained periodically to have fresh water put in.
On older pools that were built in the 70-80’s the main drain line hooks up to the bottom of your pool skimmer. With this plumbing setup your main drain would have no positive suction since water takes the easiest path of resistance. Most of the water travels through your pool skimmer instead of your main drain.
New Pool Drains
All new pools built now are required to be installed with anti-entrapment main drain setup and are installed on a separate line. These is a double main drain setup that is connected together. These drains are the safest for kids and for preventing anybody or anything from getting suctioned to your main drain.