Drip, drip drop… No, it’s not those pesky little April showers, but it might be the sound of your leaky boiler.
Unlike strange boiler noises and boiler pressure problems, a leaking gas boiler doesn’t just affect your central heating. It can be a home emergency often requires attention sooner rather than later to ensure it’s safe.
From the relatively mundane to issues only a certified engineer can fix. Fear not! HUG are on hand to help you diagnose (and hopefully fix) your watery woes.
Why is my boiler leaking water?
First things first: let’s start by trying to find where the leak is coming from. This will help you decide whether you should attempt to fix the problem yourself, or whether to call a certified engineer – something we strongly recommend in some cases.
In either scenario it’s helpful to make like Sherlock Holmes and find out as much as possible about the problem at hand.
Water is leaking from the pressure valve
One of the easiest leaks to identify and, more often than not, the simplest to fix, is water leaking from the pressure valve. This can happen when the pressure in your boiler is too high and let’s face it, who likes working under too much pressure? Your boiler certainly doesn’t.
While we humans have plenty of ways to let off steam – knitting, canoeing – whatever takes your fancy – boilers can cope with some fluctuation in pressure but not if that pressure becomes too excessive.
If all that extra pressure isn’t expelled via the boiler pipe (technically referred to as the pressure release pipe), it may begin to seek passage through less conventional routes, et voila! A leak.
Luckily, if your boiler is leaking water due to being over-pressurised, there’s a good chance it can be easily fixed. Simply reducing the pressure in your boiler to a safe level (usually between 1-2 bar) should dry things up in a flash.
Try releasing some of the build-up by adjusting the filling loop and bleeding your radiators until the pressure returns to normal.
If after all this you find your boiler is still leaking, or for no apparent reason excessive pressure has returned, there could be a problem with the expansion vessel or release valve (the thing that’s designed to relieve excessive pressure) so who you gonna call? That’s right! A Gas Safe engineer.
Water is leaking from underneath
Another relatively easy problem to diagnose is water leaking from underneath your boiler, specifically from the fittings or joints on the pipes. To make sure that this is the case, and water isn’t just leaking from the boiler and dripping down from pipe fittings, simply take a cloth and dab the area dry. If, after a minute or two, water seems to appear out of nowhere, hey presto! You’ve found the problem.
Leaky components underneath your boiler happen for one of two reasons, either you’ve had some bad plumbing installed by a certain Del Boy Trotter (probably not the case if your boiler is at least a few years old and has been in situ for some time) or, your boiler is simply showing its age.
Over time, continuous fluctuation in the flow of hot and cold water causes the pipes under your boiler to repeatedly expand and contract. In itself this isn’t a problem – the pipes under your boiler are specially designed to cope with this type of stressor but eventually, once-watertight fittings can find themselves becoming loose.
The good news is, if all the components look to be in otherwise good health (e.g. not showing any significant signs of corrosion,) there’s a good chance a quick quarter turn clockwise on the nut or nuts where the water seems to be leaking will tighten things up nicely.
If after trying this, water still continues to leak, the PTFE tape that was used to create the watertight joints might need replacing, in which case it’s brews at the ready and waiting for an engineer.
Water is leaking from the internal seals
Identifying water that’s leaking from inside your boiler system can be a little trickier.
Over time, the constant heating and cooling of your boiler’s internals can cause the rubber around your heat pump to dry out and become brittle, impairing its ability to do its job effectively (keeping water inside your central heating system.) Worn out rubber can also become easily damaged by debris flowing through your boiler system, both causing your boiler to leak water.
If safe to do so, try and locate the seals, without removing the cover to your boiler, great! You should be able to tell if this is the root of your problems. If not, DO NOT attempt to remove the boiler cover yourself. Doing so contradicts good gas safety and could leave you exposed to a myriad of potentially fatal hazards including boiling water, exposed electrics, carbon monoxide and other gases.
Instead, arrange to have an engineer come out and take a look for you despite what you find (or not as the case may be). You may be relieved to know that they will need to carry out the repairs anyway, so getting your boiler fixed doesn’t necessarily rely on your skills as a detective.
While all that might sound pretty scary, don’t panic just yet. If only the seals need to be replaced, a repair should be relatively inexpensive. If, on the other hand, the heat pump also needs work, you should prepare yourself for a slightly higher price tag (albeit less than that of a brand new boiler).
Water is leaking from the temperature valve
If you find that water is leaking from your boiler’s temperature valve, this could indicate that the temperature in your boiler is too high.
On the face of it, simply turning down the temperature of your boiler might seem like the obvious solution, but this rarely works – by all means, give it a go and cross your fingers in the hope that it works – you might be one of the lucky few.
More likely is that your boiler has developed a fault with its temperature probe – something that will need replacing by a registered engineer. However which way you look at it, your boiler’s days are probably numbered and it might be worth making a start on its obituary.
Water is leaking from a crack in the boiler tank
If you identify water leaking from a split or crack in your appliance (again this might need the help of a certified engineer to diagnose) it should be pretty obvious what the problem is.
It’s not uncommon for your boiler to develop some imperfections over time, but usually these are mostly cosmetic. In some cases, though, the constant heating and cooling that your boiler facilitates can result in cracks or splits – the end result: leaking.
Sadly, repairing a cracked or split boiler tank can cost significantly more than a brand new boiler installation, so it could be time to call curtains on your existing set up.
Water is leaking from anywhere else
We’ve already mentioned a few of the most common causes for a leaky boiler, but this list is by no means exhaustive. If you’ve been unsuccessful in isolating the source of your leak, or the leak is not coming from any of the places mentioned above, there’s a good chance corrosion is to blame.
Gas boilers are more prone to corrosion in hard water areas, but even boilers with the best water supply can suffer. Nevertheless, corrosion doesn’t have to signal the death of your boiler. This depends entirely on the level of corrosion and how widespread the issue is.
If corrosion is isolated to a small handful of components, replacement parts can often be a very affordable option.
If however your boiler appears to have contracted a severe case of the “rusties” and the heat exchanger or central heating has been affected we’re sorry to tell you your boiler may very well be beyond repair, and a replacement system is your only option.
What should I do if my boiler is leaking water?
It’s important to remember that whatever the cause of your leaky gas boiler, it’s probably wisest to deal with the issue toot sweet. Not only can some of the issues mentioned above stop your boiler functioning properly, a leak can cause a lot of non-boiler-related damage much worse than a soggy floorboard.
But it’s not all doom and gloom! With just a few questions and our innovative online system, we can help you find the perfect replacement boiler based on your budget and living circumstances. In most cases we can even have your new boiler installed in less than 24 hours*.
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