Toilet runs constantly or randomly refills on its own

Common Causes

1. Worn or warped flapper (most common) — hard water accelerates flapper deterioration
2. Float set too high, causing continuous overflow into the bowl
3. Worn fill valve seat
4. Flush valve seat corrosion (hard water deposits) preventing flapper from sealing

What You Can Try First

1. Remove the toilet tank lid and observe: if water is running into the overflow tube, the fill valve float is set too high — bend the float arm down or adjust the float adjustment screw
2. Check the flapper: put a few drops of food colouring in the tank; if colour appears in the bowl without flushing, the flapper is leaking — replace it ($8-15 at any hardware store)
3. Shut off the supply valve at the wall, flush to empty the tank, and swap the flapper
4. If the fill valve runs continuously even with the float at the right level, replace the fill valve (Fluidmaster 400A is the standard — $15-25)
5. A running toilet can waste 200+ litres per day — worth fixing promptly

When to Call a Pro

• Toilet is rocking or loose at the floor (possible wax ring or flange failure)
• Water is visible on the floor around the toilet base
• Multiple attempts to adjust the fill valve and flapper have not worked
• Tank is cracked

Alberta Context

Hard water in Innisfail and area causes mineral deposits that warp and harden flappers faster than average. If you are replacing your flapper for the second or third time within a few years, consider a Korky or Fluidmaster "hard water" resistant flapper, or address the root cause with a water softener.