A constantly running toilet isn’t just annoying — it can waste hundreds of litres of water and increase your bills. Fortunately, in many cases, you don’t need to call a plumber right away. Our latest blog and video shows how to diagnose and fix a running toilet in just a few easy steps.
Why Toilets Run Continuously
A running toilet usually means one of the internal components is failing to do its job properly. The three most common culprits are:
- The float – controls the water level in the cistern
- The fill valve – refills the cistern after a flush
- The syphon seal/washer – stops water escaping into the bowl when not in use
If any of these fail, water keeps leaking from the cistern into the bowl — and the toilet keeps trying to refill itself.
Step-by-Step: Fixing a Running Toilet (As Seen in Our Video Below)
1. Lift the Lid
Carefully remove the cistern lid and set it aside. Inside, you’ll see the float mechanism, fill valve and flush assembly.
2. Check the Float
Gently lift the float arm. If the water stops running, the float may need adjusting to sit lower in the tank.
3. Adjust the Fill Valve
Many modern toilets have adjustable fill valves. Lowering the valve slightly can stop the system from overfilling and triggering the overflow.
4. Inspect the Syphon Seal/Washer
If water is leaking into the bowl, the rubber syphon seal/washer at the base of the cistern may be worn or warped. Replacing this is often a quick fix and widely available at DIY stores.
5. Test the Flush
After adjusting or replacing any parts, flush the toilet and watch to see if the water stops refilling once the cistern is full.
When to Call a Professional
If your toilet continues to run after these steps, there could be:
- A faulty fill valve needing replacement
- A cracked overflow pipe
- More complex internal damage
In that case, it’s time to call a qualified plumber. At Heating & Plumbing Doctors, we offer fast, friendly service across Coventry and the Midlands — and we’re only a phone call away.
Why This Matters (Especially in the Summer)
During summer months — especially in heatwaves — UK households use more water. A running toilet can push your usage even higher, and in areas with water restrictions or metered usage, that’s something to avoid.
Fixing the problem early is good for your wallet and the planet.
Need Help from the Pros?
If your toilet is still causing problems or you’d rather let the experts handle it, contact Heating & Plumbing Doctors today. We cover everything from emergency repairs to full bathroom plumbing, with fast appointments and friendly advice.
