Toilet Running Non-Stop? Here’s What Could Be Happening.

Is your toilet always running? Does it seem like it flushes automatically? Have you looked everywhere, but found no signs of leakage? Have you assessed the tank flapper? Is it working just fine? The sound of your toilet always running isn’t just annoying, but also wastes water and works against a long life for your plumbing. Is there leakage in your toilet bowl?

Read on to find out what could be triggering your toilet to run all the time and what a plumbing contractor can do to solve it.


8 Possible Cause of a Constantly Running Toilet

Toilets are built with flappers to seal water getting into the tank. The flapper lifts whenever a toilet is flushed, allowing water to flow into the bowl from the tank. The flapper then falls back to its initial position the moment water in the tank reaches a certain level, re-sealing it.
However, if a flapper builds up sediment or becomes brittle, your toilet will appear to randomly auto flush. When this happens, the flapper fails to fully seal water in the tank. As a result, water flows slowly into the bowl from the tank in drips. When sufficient amount of water leaves the tank into the bowl, the vacuum triggers the filling mechanism to refill the tank.
On the other hand, enough water in the toilet bowl triggers the self-siphoning mechanism, causing the bowl to drain its contents into the sewerage system.

Other Possible Causes

  • A crack in the part of the overflow tube under water can also cause water to leak from the toilet tank into the bowl. The leakage can go on unnoticed, leading to the float getting low enough to create an opening for more water flow and thus filling back up suddenly.
  • The plastic nut holding the flapper could be loose, leading to water leakage from the tank into the bowl.
  • A damaged toilet water stopper/controller can also cause the leakage.
  • High iron concentration in water can jam the flushing systems, causing leakage and thus the automatic running toilet issue.
  • Leaking valves due to high pressure.
  • The main tank is being cleaned or supplied with water.
  • Long refill tubes extending below the filling line siphon water from the tank into the bowl.

How to Assess Flapper Leakage

1. Add 3 to 5 drops of food color into your toilet tank when it’s filled with water
2. Stir the water to mix the food coloring
3. Look at the bowl for any coloring that might get there if there’s leakage

The presence of colored water in your bowl is an indication that your flapper is leaking. Otherwise, the problem could be on the supply side of the system. Temporarily lower the level to prevent the colored water from going through the overflow in case the issue is coming from the supply letting in water, meaning no leakage.

Possible Solutions

  • Add a link to the chain to prevent it from exerting too much pressure upwards on the flapper
  • Replace the flapper with a flat rubber flapper if it no longer seals properly; it costs about $5 only
  • Use a short refill tube that goes into the overflow tube
  • Assess the stopper for anything that might block it, causing it not to seal completely

Contact us to find a professional plumber near you to assess your toilet and help fix the automatically running flushing unit problem