How to Find A Leak in the Toilet Tank

When the fill valve in your toilet turns on and off during periods of non-use, it is refilling the tank due to water loss. This is called “Ghost Flushing”. Such water loss, if undetected, can add to your water bills. In order to determine the location of the leak, you will need to have a pencil and a flash light for this procedure. If are not seeing water on the floor or outside of the toilet tank then the water loss is at the flush valve, (the overflow pipe flapper and drain seat). When you cannot seem to find the leak we recommend you do this simple water test:

1). Turn the water off at the wall. Do not flush the toilet. Leave the tank complete.

2). Mark the level of the water with a pencil. (This is a reference point of past water level). Check the tank every hour or so. Each time you check the tank and the level of the water has dropped from the past pencil mark, mark the new water level.

3). ultimately, you will check the tank and if the water level has not changed from the past pencil mark, then the leaking has stopped.

4). At this point follow the surface of the water to the flush valve. The leak is slightly above the surface of the water on the flush valve.

For example: a). If the water level stops at the lower lip of the flapper, you need to clean or replace the flapper. The flush valve seat may need to be cleaned in addition; b). If the water level stops anywhere above the flapper, check the refill tube. If the refill tube is inside the over flow pipe and it is below the water level of the tank it will siphon water. You will need to shorten the hose so the end is above the water level of the tank or use the angle adapter with clip supplied with the fill valve; c) The bottom of the metal over flow pipes are threaded. Check for pin holes or corroded threads. Remove and replace the over flow pipe if necessary; d). If the water drops below the flapper, check the tank for fractures in addition as the condition of the rubber washer. If the washer has vertical fractures in it this would cause leaking. The flush valve may be loose. If so, tighten or replace it.

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