Replacing an Old Boiler

Having your boiler replaced isn’t something you want to put yourself – or your purse – through more often than is necessary. Luckily, boilers are tough pieces of machinery and can last 15–20 years if maintained properly. That’s one reason why you should have it checked and serviced every 12 months by a professional boiler installer — the other reason that the warranty usually demands regular services to keep your guarantee valid.

However, if your boiler has seen better days, is no longer running efficiently, or keeps breaking down, it may be time to look at a replacement. That’s why we’ve put together this handy guide, to tell you everything you need to know about home boiler replacement.

Why are you replacing your boiler?

Firstly, let’s look at the most common reasons for replacing your boiler and work out the best way to proceed.

It’s on the blink

You’ve just run a nice hot bath, stepped in and realised it’s stone cold. That’s it — time to replace my boiler. Well, not so fast. The first thing you should do is check the digital readout — if it has one. If it’s giving an error message, it could be that your boiler has tripped out. In this instance, head to Google and search the error message or visit the manufacturer’s website. This is always worth doing as a lack of hot water could be as simple as needing to top up low water pressure or resetting the system.

If you’re unsure what’s causing the issue, get in touch with a qualified boiler specialist and let them have a look. It could well need a repair, so it’s best to check before paying out for a central heating boiler replacement.

It’s definitely beyond repair

If you call an expert and they decide the repair costs would be greater than buying a new boiler, it may be time to take the plunge. Speak with the fitter and they’ll be able to advise you on your next boiler. It’s possible that your existing boiler wasn’t the right type for your household anyway, in which case you’ll need a different one — this could provide you with a more efficient model and end up saving you money in the longer term.

It’s old and inefficient

The older a boiler is, the less efficient it is. That comes from a combination of wear and tear plus the better technologies and regulations that keep improving boilers’ running costs. Your 30-year old model might be steadfastly supplying you with hot water — it might even have sentimental value — but the chances are you’re probably paying higher bills and leaving a bigger carbon footprint.

Your needs are changing

Building an extra bathroom? One of your elderly parents moving in? Kids flying the nest? Different household sizes and hot water demands call for different types of boiler. We’ve written about choosing the right boiler for your needs, so have a look at that article before you make up your mind, or speak to an expert.

An important thing to note is that different boilers have different systems, and the costs will change accordingly. Generally speaking, if you’re changing from a combi boilerto a system boiler, or from either of those types to a conventional boiler, you’re going to need extra piping and tanks. However, if you’re going the other way (conventional > system > combi) you’ll usually be able to use most of the existing hardware (apart from the boiler itself), resulting in a lower cost boiler home replacement.

You’re selling your home

There are two types of home-seekers: those looking for a cheap doer-upper; and those who want to move in, unpack their boxes and start living. Obviously the second group will be prepared to pay more than the first, so giving them as little as possible to do when they move in will boost your home’s value. That’s why it can easily pay for itself if you get new carpets, wallpaper, guttering, glazing… and — you guessed it — a new boiler.

By getting a new boiler, you’re simply making the new owner’s move less of a hassle – and they’re prepared to pay for it. Also, note that if your boiler is old and has a low efficiency rating, it will definitely come up on the survey, and you could scare away buyers looking for an easy transition to their new home.

If you’re after a quick sale at any price, you might actually benefit from leaving the old boiler in place. Professional developers (who buy and renovate houses for a living), know the best places to buy a boiler and will almost certainly have relationships with central heating fitters, so they won’t be influenced by your new heating boiler replacement.

Why modern boilers are more efficient

As time has progressed, boilers have become more reliable, more efficient, smaller and easier to control thanks to technology and legislation, and that trend will no doubt continue. To enforce greener home heating, any boiler installed since 2005 in the UK has had to be a condensing boiler. But what does this mean?

Before condensing boilers, the gas flame heated the circulated water, which in turn heated the hot water and central heating you use in your home. The flame certainly did its job, but the hot gases emitted would be exhausted to the atmosphere, often at more than 200 °C — a huge waste of heat energy.

Modern condensing boilers force those hot gases through a series of baffles, where they pass around pipes containing the cool water returning from the radiators or hot water system. This has two effects: it starts to warm up the cool water; and it cools down the hot gases. So by the time the “cold” water passes over the flames, it’s actually already been warmed up quite a lot.

Essentially, that means much less power is needed from the flames to get the water up to its operating temperature, resulting in a much more efficient boiler. In fact, it can work so well that the hot gases condense (turn into liquid), hence the name.

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