Is there an automatic pump ssytem to drain a pool with liner if it fills too much?

Yes, there are automatic pump systems that can drain a pool with a liner if it fills too much. These systems are typically connected to a float switch, which is a sensor that detects the water level in the pool. When the water level reaches a certain point, the float switch activates the pump, which then begins draining the pool water.

Some of these systems also include a timer, which allows you to set a specific time for the pump to turn on and off. This can be useful if you want the pool to drain at a certain time of day, such as during the night when electricity rates are typically lower.

Automatic pool drain systems are relatively easy to install and can be purchased at most pool supply stores. They are a great way to prevent your pool from overflowing and causing damage to your property.