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How much is a new boiler?

How much is a new boiler?

The average cost of a new boiler installation in Milton Keynes, Luton, Dunstable & St Albans depends on the type of boiler that you choose. Here’s what you might expect to pay:

  • Combi: £1,600 to £3,200
  • Heat-only: £1,400 and £2,400
  • System boiler: £1,500 to £2,600

But what goes into these prices? 

Why does getting a boiler replacement in Milton Keynes cost this amount of money? 

Breakdown of Boiler Installation Costs

The amount that you ultimately wind up spending on your boiler depends heavily on your current circumstances. Very few people need to install a furnace from scratch. Mostly, they need to replace an existing unit. 

The price you pay, therefore, comprises two things: the cost of removing the old boiler and that of replacing it with a new one. 

Typically, a combi swap where you pull out of the oil boiler and replace it with a new one costs around £2,000. 

If you are removing a combi boiler from one location and installing it in another, then the costs can rise to £3,000. 

If you want to replace a heat-only boiler with a combi, then you’ll also spend more because of the cost of making new connections. Prices usually fall around the £3,000 mark, similar to changing the boiler location. 

Why Do Costs Vary So Much?

Boiler price costs vary considerably, which can be confusing. Part of the variation in cost depends on who provides the installation service – a sole trader, small business in the local area, a big company, or an online company with a subcontractor network. Different business setups have varying overheads, and this impacts the prices they charge. 

Sole Traders

Sole traders perform a sizable chunk of total UK boiler installations. Typically, they comprise a single operative with a specialist background in boiler and gas safety. 

Sole traders usually have much lower overheads, so their prices tend to be more affordable than other options. They also typically have lower labour costs than engineers from the big firms, again providing customers with savings. 

There are downsides to using their services though. If something goes wrong with the installation, then you may be waiting for a long time for them to come back and fix the problem. It all depends on their schedule. 

Online Companies

Online companies are a relatively new player in the boiler-fitting market. These agencies don’t hire any operatives directly. Instead, they create networks of sub-contractors to whom they farm out work. Who you ultimately get is very much a function of the area in which you live. 

The purpose of these online services is to give customers quotes without the need for a home visit. The idea is to increase the competition between suppliers and get homeowners a better deal on boiler replacement. 

Prices are lower for two reasons. Firstly they aggregate fitters into one place, making it easy to compare them. And, second, because they bulk buy boilers before installing them, they reduce costs. Customers, therefore, can sometimes bag substantial discounts. 

Small, Local Businesses In Milton Keynes, Luton, Dunstable & St Albans

The third option is to choose a small local business in Milton Keynes. These are not sole traders or handymen. Instead, they’re professional firms with multiple accredited people who specialise in boiler installations. Some have office staff, but many do not. 

The price you pay here depends considerably on whether you’re dealing with a barebones company or one looking to create a brand. Some of these outfits are just two or three people operating under a limited liability company structure. Others are growing businesses that have people both out in the field and the head office. 

These companies tend to have higher overheads than sole traders, but they also have higher volume, meaning that they can spread the costs across more customers. Prices, therefore, tend to be relatively competitive. 

What’s more, many of these firms offer additional security and guarantees versus a sole trader. So, for instance, they might provide a one-year warranty on all installations or promise to return in 48 hours if there’s a problem with the unit they install. 

Big Companies, Such As British Gas

Big companies, like British Gas, tend to charge considerably more than their smaller rivals – sometimes up to 50 per cent. 

The reasons for this come down to two things: protection for homeowners and high overheads. 

The big boiler installation firms must pay back-office staff wages, advertising costs, interest payments on loans, and full-time engineers. Customers are willing to pay more because of the sense of security that they get. But they ultimately spend more money compared to the other methods that we’ve discussed above. 

In return for paying more, customers get professional customer support. You know that if there’s a problem with your boiler, there will always be somebody you can call to come and fix the problem. 

Interestingly, you no longer need to go directly to the big companies, like British Gas, to get a quote. Many will now tell you what a boiler replacement will cost online. In general, going online will help you save money. But beware: you’ll still likely pay a lot more than if you went to a small company. Mostly, these sites compare the prices of market leaders, not those of the smaller players. 

Should You Get An Online Quote Without A Home Visit?

Bringing the pricing process for getting a new boiler seems like a good idea in principle. You go online, enter your details, and then get a quote from the provider, based on what you tell them. 

But there is a reason firms used home visits in the past and still do today: it allows them to predict the final price more accurately. 

While going online is convenient, the vast majority of people in the industry would recommend that you get a home visit. Most small companies and sole traders offer “no obligation” quotes. You can get a home visit, but you don’t have to hand over any cash. Some homeowners like to find out what they think it will cost to carry out work and compare it to what the internet says. In-person quotes can be considerably lower. 

Boiler Cost Installation Scenarios

So far, we’ve talked about the average cost of a boiler and how the price changes depending on who you hire. But, let’s face it, it is all rather abstract. 

The following examples should help you get a better sense of how much you’re likely to pay. It very much depends on your current circumstances. 

How Much Is A New Combi Boiler?

Combi boilers are those that provide heating for your central heating system and hot water tank. They are, therefore, a do-it-all product, centralising everything into a single unit. You find them in new builds most commonly. 

When it comes to replacing a combi boiler, there are two possible scenarios: 

  1. Replacing an existing combi boiler with a new one
  2. Replacing a regular heat-only boiler and hot water cylinder

Let’s deal with option one, first. As we discussed in the introduction, the cost of replacing an existing boiler in the same location is different from the replacement boiler going to a different site. Typically, the cost of swapping the old furnace out and replacing it with a new in the same place is around £2,000 and takes about a day. Moving it to a different location costs around £2,600 and takes a day and a half. 

Replacing a regular heat-only boiler with a combi is, typically, a far more complicated operation, often requiring extensive plumbing work. The cost usually comes in at around £3,200 and takes approximately two and a half days. Redirecting the hot water pipe to the new boiler is the most time-consuming aspect of the process. 

How Much Does A Heat-Only Boiler Cost To Install? 

Heat-only boilers only heat the central heating system. A separate cylinder heats the hot water. For this reason, these systems tend to cost a bit less money to replace. 

Here, again, two possible scenarios apply to your home: 

  1. Replacing an existing heat-only boiler with another at the same location
  2. Replacing a heat-only boiler and putting it in a new place. 

Replacement in the same location typically costs around £1,750 and takes about a day. Replacing it but putting the new boiler in a different place costs around £2,200 because of the additional plumbing requirement.

A significant component of the price here is the labour, not the boiler. You can usually pick up a standard heat-only for around £750. The rest of the cost is for the work and the tools. 

How Much Does A System Boiler Cost To Install?

System boilers are relatively rare in flats and regular homes. Typically they provide heating to multiple household units and work with an unvented hot water tank to provide hot water. They are much more potent than standard boilers and, therefore, more expensive to replace. 

When it comes to replacing a system boiler, therefore three possible scenarios that might apply to you: 

  1. Replacing an existing system boiler with a new one
  2. Replacing a combi boiler with a system boiler and unvented hot water tank
  3. Replacing a heat-only boiler with a system boiler and unvented hot water tank

The differences in price and complexity are considerable here. 

If you want to replace an existing system boiler with a new one, the cost is £1,950 on average, and the work takes around a day. Replacing a combi boiler with a system boiler will set you back around £4,600 and take roughly two and a half days. The cost of replacing a heat-only boiler is slightly less at £4,200 and takes around two days. 

How Much Does It Cost To Replace A Back Boiler? 

Back boilers became popular throughout Britain in the late 1960s. 

An open fire heats a boiler behind a wall. It then pumps water through the central heating system. You can no longer replace a back boiler with a similar one. Regulations state that you must either use a combi, system or heat-only. 

Here are some of the scenarios that you’re likely to encounter if you have this variety of boiler: 

  1. Replacing a back boiler with a separate hot water tank with a combi boiler
  2. Replacing a back boiler with a heat-only boiler and keeping the existing water tank

Replacing a back boiler with a combi boiler is the most attractive option for most homeowners. The average cost for this is around £3,200 and takes roughly two and a half days. Replacing a back boiler with a heat-only boiler costs £2,775 and takes about two days. 

Boiler Unit Costs

So far, we’ve looked at the combined cost of buying and installing a boiler. But, of course, there are two primary components of the price that you ultimately wind up paying: labour and the unit itself. 

How much you pay for a boiler depends heavily on the model you buy. In the discussion above, we calculated the estimated costs based on installing a mid-range boiler. However, you can buy both entry-level and ultra-premium units, just like in any other market. 

Boiler unit costs fundamentally depend on the quality of the internal components. The more expensive versions use premium parts that help to last longer. 

They also come with additional support. As you move up the price range, for instance, the length of the warranty increases. Entry-level boilers typically offer between two and five years of cover for manufacturing defects. Economy boilers provide five to seven years of protection, and premium units sometimes go as high as ten.

You also get better after-sales-care the more money you spend on the unit. Entry-level boilers tend to have strict manufacturer-imposed conditions for them to honour the warranty. You have to prove that whatever caused the boiler to stop working was the fault of the vendor – and that’s not always easy.

The next level up is “economy.” Here you still have to meet terms to get a replacement unit, but they’re not usually as strict as those imposed when you buy a cheap boiler. 

Mid-range and premium boilers usually have what vendors call a “no-quibble” guarantee. Here they promise to repair or replace if you have a problem, no questions asked. 


For those who are interested in energy efficiency, boilers differ here too. All modern boilers are surprisingly efficient, but as you increase the quality of materials, you find that the numbers creep up. 

  • Entry-level boilers typically achieve 89 to 91 per cent efficiency
  • Economy boilers offer 89 to 91 per cent efficiency
  • Mid-range and premium both offer between 92 and 94 per cent efficiency


Now for the most critical detail: the price. 

Here’s a rundown of what you can expect to pay for a combi boiler in each market segment: 

  • Entry-Level – £685
  • Economy – £775
  • Midrange – £975
  • Premium – £1150

As you can see, the cost of premium boilers comes in about double the cost of an entry-level version. With that said, you get a much better product offering higher efficiency, a more extended warranty, and no-quibble after-care. As you move up the price range, you also get things like weekend callouts and manufacturer-supplied engineers. 

Why You Shouldn’t Choose A Boiler That Is Too Large

A lot of people believe that it is a good idea to choose a boiler that is a little larger than they need. What’s the harm in having extra capacity? It seems like a sensible idea. 

Unfortunately, it can backfire. Every manufacturer creates boilers designed to perform at a specific capacity for maximum efficiency. If the owner deviates from the specification too much, energy conservation can plummet, and bills go up. 

Pairing the wrong boiler with your home can actually be a lot more damaging than you might imagine. 

Most boilers heat water to a standard 70 degrees. They then pump it around the radiator system where it loses at least 20 C to the environment, before returning to the boiler. For a condenser to work, the returning water must be 50 C or less. If it is more, then the furnace can’t work in the 90 per cent efficiency range – putting up your bills. 

If your boiler is too large, then the condensing phase will not work, and you’ll lose efficiency. 

The average UK home only needs between 6 and 8 kilowatts of heating energy. But the average output is 15 kilowatts, implying most boilers are oversized. 


Working out the precise cost of a boiler is a challenging process. Not only do you have to consider who you’re buying from, but also the quality of the boiler and your existing setup.

Typically, the cost of the unit runs between 28 and 60 percent of the total for the installation. The rest is the cost of labour. 

It is possible to replace your boiler for a relatively small amount of money. Still, you could end up paying higher costs over the long-run in repairs and maintenance. For most people, a mid-range combi boiler is an optimal solution, offering the best price-performance ratio. 

Your New Boiler.Com is Owned by Wayne Bettess