New Back Boiler Replacement – Quotes & Prices

Back boilers are, to put it frankly, relics from the 1960s, 70s and 80s. They sit behind a gas fire or stove, tucked away in the wall, providing heating and hot water for the home.

Old Back Boiler vs New Combi Boiler
Old Back Boiler vs New Combi Boiler

To give them their dues, they have a well deserved reputation for reliability. They have far fewer components and generally live longer than modern boilers.

The snag is that they are no longer the best option in terms of energy efficiency when compared to modern boilers, are no longer being produced and as such are rarely advised as new installations. This means that, despite their talent for endurance and long years of service, sooner or later you and your back boiler will need to part ways.

Just like any long term relationship, breaking up can be a frightening transition. Whether the boiler has given up or you have decided it’s time to move on to a newer, more energy efficient model, most professionals will advise you to move on to a Combi boiler.

Need to replace your back boiler with a Combi?

We can provide you with up to 3, no obligation quotes from qualified engineers in your area.
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Why Replace Your Back Boiler with a Combi?

Despite your happy memories together, it is time to face some harsh realities about your back boiler. It is generally considered an outdated system that is expensive to install and less energy efficient. There are no condensing back boilers being manufactured today and many that still exist are over 30 years old. So what’s the answer?

The most popular solution is to replace a back boiler with a Combi boiler as it is:

Energy efficient. Typically, a back boiler provides only 78% energy efficiency which is below the government’s minimum requirement of 86%. Many modern boilers can achieve efficiency of 90% and more.

Cheaper to run. The energy wasted by a back boiler is costing you money. Replacing with a modern boiler with a higher efficiency rating could save you up to £320 a year.

Safer. An unused and empty back boiler can be dangerous as, if heated, pressure can build inside causing an explosion.

Cheaper and simpler to install. To replace back boiler you will need to remove the old one from the wall which can be very messy and expensive. Generally it is cheaper to install a modern Combi boiler elsewhere in your home.

More compact. A back boiler requires two tanks to be kept somewhere in your home whereas a Combi boiler is a single wall-mounted unit.

Need to replace your back boiler with a Combi?

We can provide you with up to 3, no obligation quotes from qualified engineers in your area.
Get a Quote.

What is a Back Boiler?

A back boiler fits in the recess behind a fireplace or gas fire. It uses the heat generated to produce hot water for central
heating and domestic use throughout the home. The boiler itself is hidden behind the fireplace but needs a separate water
tank and hot water cylinder to be stored somewhere else in the home.

Why were Back Boilers so Popular?

In the 1960s, 70s and 80s a back boiler was the best choice for many homes when compared to the traditional floor standing boilers that were roughly the size of a washing machine! At the time a back boiler was the cheaper option to install and was more energy efficient.

The back boiler relies on a very simple system with few components when compared to modern boiler technology and, as a result, has a reputation for reliability and endurance with many still operating today. It can also improve the energy efficiency of the fire or stove it is attached to. If a back boiler is still operating safely, it is possible to maintain it with regular servicing and avoid the cost of changing to a modern Combi system.

However, you also need to consider that sticking with a back boiler is less energy efficient and will cost more in energy bills.

Why aren’t Back Boilers as Popular as they used to be?

As with all technology, central heating systems have moved on since the back boiler’s heyday. While its only competition used to be the huge, floor standing unit, the back boiler is now overshadowed by the modern, compact Combi which is both safer and more energy efficient.

In truth, the arrival of this shiny, modern day competitor was just the beginning of the back boiler’s demise. In 2005, in an effort to improve both boiler safety and the UK’s energy efficiency, the government introduced new regulations. From that point all boiler installations – replacements and new builds – had to be condensing models. As there were no condensing back boilers on the market at that time anyone who wanted/needed a new boiler had to install a Combi.

Combi boilers are far more efficient and take up much less space as they don’t need a separate tank and hot water cylinder. Generally, a new back boiler is only fitted if it will be too difficult to change ta different system e.g. older homes with incompatible pipework.

Finally (as if there isn’t reason enough already) homes with back boilers often also have rather unattractive gas fire fronts that aren’t so popular with those of us concerned with interior design. The changeover to a Combi boiler can mean the opportunity to rid your home of an eyesore you’ve been putting up with for years. A superficial concern, yes, but a nice bonus for many.

Need to replace your back boiler with a Combi?

We can provide you with up to 3, no obligation quotes from qualified engineers in your area.
Get a Quote.

Is it Possible to Install a new Back Boiler?

Although not usually advised, it is possible to repair an existing back boiler. So if installing a Combi boiler is not an
option for your home, all is not lost.

Firstly, it may be possible to carry out repairs if the relevant components are still in production. For example, over 80% of back boilers installed were Baxi Bermudas which were manufactured up until 2015 when it was discontinued. The company will still provide replacement parts if needed. If you choose this option your back boiler will need regular servicing to keep it functioning for as long as possible.

Secondly, there are rare occasions when a modern boiler isn’t compatible with a home’s pipework or structure; in that case, a professional engineer may advise you to opt for a replacement back boiler.

However, in most cases it is both cheaper, safer and more convenient to install a modern Combi boiler.

What is a Combi Boiler?

A Combi (combination) boiler is the most compact boiler on the market as all the elements are contained in a single unit. There is no need for a water tank or storage cylinder as, rather than keeping a store of hot water, the Combi heats water on demand. No more waiting for the cylinder to refill. They take up very little space in the home and are usually mounted on a wall in the kitchen or utility room.

They are the most popular type of boiler in the UK and, as they don’t expend energy keeping surplus hot water, they are the most energy efficient. The only potential drawback to a Combi system is that it relies on the mains pressure for water flow. For homes with a weak mains pressure this can present a problem, but it is possible to fit a pump to improve this.

To find out more about replacing your back boiler you will need a Gas Safe registered installer. Get a quote from engineers in your local area.

Dangers of Disused Back Boilers

A disused back boiler can be a real danger in your home. Even if the boiler is empty it will retain residual moisture and if the fuel burner in front of it is still in use, it will heat the boiler and create steam. If the boiler is not in an open vented condition (i.e. sealed) internal pressure will build which can result in an explosion. Over the years incidents like this have caused several serious injuries and even one fatality.

Additional risks associated with disused back boilers include the corrosion and fracturing of old pipework which could pass harmful gases into other areas of the home or the pipework reaching such a high temperature that it creates a fire hazard. Also, as the back boiler sits within the home’s wall the continual expanding and contracting of the old boiler casing under high temperatures may cause structural damage to the home.

If you have a disused back boiler in your home we strongly recommend that you seek professional advice about protecting your home and possibly removing the boiler.

Just Get a quote from Gas Safe registered engineers in your area who can advise you.

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