It’s only natural for things around your home to break after prolonged use. This goes for your water supply fixtures, as well – water tanks, boilers, toilets – what happens when there’s a fault with either of them and they begin to overflow? Well, if it weren’t for overflow pipes, the answer would be a flooded room and a damaged floor.
An overflow pipe leaking is a sign of an overflow pipe doing its job. But there’s always a reason behind the leak. And we’re here to teach you how to identify the underlying issue and what you can do to solve it.
So, if you:
Then keep on reading, because this post is just for you!
Before we get into the issue itself, it’s important to understand what an overflow pipe is. It’s a pipe connected to a cistern or water tank in your home, most often leading to the outside. Its purpose is to let any excess water from the tank run outside instead of indoors, preventing damage to your home.
You can find an overflow pipe attached to the following items:
Now that you know what an overflow pipe’s purpose is, let’s find out what to do if you find that it’s leaking.
Most of the time, if an overflow pipe is leaking, the culprit is a faulty float valve. This is a component found in cold water and central heating tanks and toilet cisterns. It’s made up of a plastic or metal arm and a plastic ball attached to the end. The ball floats on top, controlling the amount of water that flows into the tank or cistern, keeping it full and, at the same time, stopping it from overflowing.
If the float valve is faulty, the water running into the tank might not shut off completely. This results in an overflowing tank or cistern, hence the leaking overflow pipe.
So, what can you do to fix this issue?
First, you need to find out where the leak is coming from.
If the pipe is located close to the ground, it’s most likely the toilet cistern that’s leaking. If the dripping pipe is at loft level, coming out of the eaves of the roof, the fault lies in your cold water or central heating tanks.
To make sure you’ve located the leak, check the water level in each water tank and cistern. If the water level is too close to the overflow point or higher than it usually is, then that’s where the leak originates.
In order to do anything to fix the problem, you’ll need to drain the water first.
For a toilet cistern, turn off the water supply by using the isolation valve. You can find it on the water pipe leading into the cistern. Grab a flat head screwdriver and turn the screw clockwise a quarter turn. Drain the water by flushing the toilet.
For water tanks, turn the stopcock to shut off the mains water. Drain the tank by running the bathroom taps. You only need to drain it enough to clear the spot where you need to work.
Now you’re prepared. But the way to fix the issue differs, depending on the source of the leak.
The leaking overflow pipe may be coming from your cold water feed and expansion tank – the large water tank in the loft – which supplies your sinks, bath, and copper cylinder. The pipe runs to the outside through the eaves of the roof and is made of either plastic, copper, or lead, with plastic being the more commonly used material.
There are two reasons why your cold water tank overflow pipe may be leaking:
The central heating feed and expansion tank is the smaller one in your loft. This tank supplies your heating system with water. Again, the overflow pipe leads to the outside through the eaves and is made of plastic, copper, or lead.
The two possible culprits for a leaking overflow pipe from a central heating tank are:
The overflow pipe of a copper (or hot water) cylinder leads into the cold water tank instead of the outside. This lets the water in the cylinder expand when heated.
If you find the hot water cylinder overflow pipe leaking, there are two possible causes:
Technically, this isn’t exactly an overflow pipe. Combination (or combi) boilers have one much like it, though – the pressure relief valve. If the boiler builds up too much pressure, this valve releases some water to lower it. The pipe is made of copper and leads to the outside of the house.
So, why is your boiler overflow pipe leaking?
As boiler repairs can be dangerous, we recommend you call a Gas Safe registered boiler engineer to carry them out and ensure the safety of your home and family.
Find out what the expert boiler engineers at Fantastic Services can do for you!
Locating a toilet overflow pipe is easy – it runs to the outside and is located directly behind your toilet. As with the water tanks, the pipe is made of plastic, copper, or lead.
If your toilet overflow pipe is leaking, it means the water supply to the cistern isn’t stopping. There are a couple of things you can do:
Unlike the rest of the pipes we mentioned in this post, bath and sink overflow pipes don’t leak outside. You might recognise these as the small openings at the back of a basin below the rim. These openings are connected to pipes running directly into the drain. Their purpose is to drain the basin if you leave the water running with the plug in.
To stop the sink from overflowing, just take out the plug and let it drain. However, if it’s filling up with water without the plug being in place, then you’re probably dealing with a blocked drain.
If you’re not a fan of DIY home repairs, or you’re dealing with an issue that requires professional help, look no further than Fantastic Services! The experienced and certified plumbers we work with will make sure any problems are expertly resolved. And, should you need boiler repair, the Gas Safe registered engineers can handle it all, ensuring the safety of you, your family, and your home. So, book your service today using our simple booking form!
Entrust the job to the expert plumbers!
And there you have it – hopefully, you’ve found the solution to your overflow problem. And, if you’re dealing with even more leaks, read our guide on how to find a leaking pipe and find out what you can do.
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Was this post helpful to you? How did you handle your leaking overflow pipe? Let us know in the comments below!
Image source: Shutterstock / Peter Baxter
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