The answer to 'pressure regulator slow draining' is that a slow-draining pressure regulator is often caused by a buildup of sediment or mineral deposits within the regulator. This can restrict the flow of water and cause the regulator to drain slowly.
Some common symptoms of a slow-draining pressure regulator include low water pressure, long wait times for the tub or sink to drain, and the regulator itself taking a long time to empty. In some cases, the regulator may need to be replaced entirely if the buildup is too severe.