Gravity Flow Toilets When the flush lever is pressed on a gravity flow toilet, water flows out through the flush valve, into the toilet bowl and through the trap, taking waste with it. The toilet’s flush lever is connected to a chain or There are several common reasons why water supply to a toilet or sink may seem inadequate. Sometimes, shut-off valves on the water lines that feed a sink or toilet may be partially closed, limiting the volume of water coming through the line. These valves are not designed to meter water flow and can affect the performance of fixtures and toilets if not fully open. Another reason water supply may seem limited is the common use of faucet aerators in new homes to restrict water flow. This conserves water and is not a defect. However, water flow can be inappropriately reduced if an aerator becomes clogged by minerals in the water wire that lifts a flapper or a tank ball that controls the flow of water from the tank to the bowl. Water moving into the bowl from the tank acts like a siphon, pulling waste and water from the bowl into the drain line. that accumulate over time. To improve flow, replace the aerator or clean it. Within a city or town, water pressure is regulated by the municipality and is not usually adjusted. Variations may occur during peak periods of demand. On private water systems (e.g. wells, cisterns), a pressure regulator valve is usually located on the outlet of the pressure tank. This valve should be set between 40 and 80 pounds per square inch (PSI) of water pressure. Why does it feel like my water supply is inadequate? Another reason water supply may seem limited is the common use of faucet aerators in new homes to restrict water flow. PLUMBING 89