Cost to Install a New Boiler

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The boiler is at the heart of almost every home and supplies hot water to the radiators and hot water taps.

How much does it cost to replace a boiler? And can you really get a return on your investment? Can an old boiler be swapped for a new one or is there extra work involved?

According to uSwitch, the typical homeowner can save between 11% (£79) and 33% (£237) per year by replacing an old inefficient boiler with a new modern condensing  system.

That means you could pay off the initial cost in as little as 9 years!

You should also remember that a new boiler may add value to the property, so you may recoup some of the cost should you decide to sell and move on.

New Boiler by Glow Worm. Costs and prices

New Glow Worm Boiler

New Boiler Cost – Straight Swap Possible?

Contrary to what many homeowners assume, it isn’t always possible to simply remove an old boiler and replace it with a new one.

Since 1st April 2005 all new boiler installations (including boiler replacements) must be done with condensing boilers. These are more energy efficient but do require some extra work and this all adds to the new boiler cost:

  1. A drainage pipe must be installed to take the excess water away, this pipe is usually taken through an external wall and connected into an external drain. This could be a simple job or it could take all day, it really depends on where the boiler is located. In some extreme cases it may be easier to move the boiler to a new location.
  2. The new regulations also state that the temperature of each room must be adjustable, so that means thermostat valves on each radiator in each room, with only a few exceptions. This is so the homeowner can reduce the temperature in any given room, for example rooms that aren’t used often. This helps to reduce heating bills and lowers carbon emissions.
  3. A new gas supply pipe may also be required, this is to comply with new rules regarding allowable pressure drops between the gas meter and the appliance. This could mean installing a larger pipe but depends on the age of the property as many houses built after the year 2000 already have a suitable gas supply pipe.

Example 1 – New Boiler and TRVs

For this quote we are assuming you have the old boiler swapped for a new condensing unit in the same location, we assume there are no issues with the outlet/drain for the excess condensation. You will be keeping the original controls and wall thermostat which are fairly modern, you can already operate the hot water for the taps and the radiators separately.

To comply with recommendations, you will have TRV valves installed to radiators (except those in a bathroom or the room with the wall thermostat) This price is for the “bare essentials” a new boiler, thermostatic radiator valves and a system flush (see how much a system can cost here). We are not assuming any new radiators, cylinders or fancy controls which will add to the cost quoted here.

For comparison, we are assuming a Baxi or Glow-Worm type boiler for a two-bed property with a total of seven radiators:

LocationSmall Business /TraderLarge Business (5+ employees)
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London Area£2750.00£3350.00
South, SW and Midlands£2250.00£3000.00
Outer Region and North£2150.00£3000.00

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Quote Comparison

As you can see from the examples above there is a huge difference between the quotes.

When we contacted our central heating installers we found a wide gulf in new boiler costs between the bigger companies such as British Gas and smaller one-man traders. There was also a big difference between the quotes depending on location, although this was more pronounced in the quotes we received from one-man type businesses.

All of the quotes were for similarly priced boilers, although British Gas did include some extra pipework on two of our houses, which no other company felt the need to replace.

To see exactly how we get prices for our cost guides, visit this page.

Example 2 – Optional Extras

TRV costs (thermostatic valves for radiators

When you have the new boiler installed you will have the option of having additional work carried out. It will be cheaper to have this work done now rather than at a later date:

  • Upgraded TRV (Valves) on all radiators £25-£50 each
  • New wall thermostat control £100-£300 assuming wiring is sound and in place
  • Remote (via app or online) control £200
  • Magnetic filtration system £150-£300
  • System flush (recommended with new boiler) £300-£700
  • New/additional radiators (£variable)
  • New hot water cylinder tank £350-£450 for standard, £650 for fancy stainless steel

Save Money by Using Controls Correctly

The central heating controls give you the option to increase/decrease the heat of all the radiators, to turn down or turn off the heat in one or more rooms, or to switch off the heat entirely when a given temperature is reached. A timer is used to switch on/off the system at a given time.

Having a modern set of controls can save you money on the heating bills and give you much flexibility.

In recent years, new apps and technology have come to market that allow homeowners to control the hot water online or via a mobile phone app. This is particularly useful for those who do not know exactly when they will be home from work. See Hive from British Gas.

Understanding Heating Controls

This video explains the difference between heating controls. Having new controls and using them optimally can save money:

Feedback on Article “New Boiler Cost”

What do you think about our guide to new boiler costs? We contacted dozens of installers and requested written quotes before we created this page.

Have you received quotes for a new boiler? How do our figures compare to yours?

You can leave a comment at the base of this page.

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2 Responses to “Cost to Install a New Boiler”

  1. TarkersFebruary 5, 2016 at 6:35 pm #

    Great website! Our house has an old back boiler fitted in the living room chimney breast and a tank fitted in an upstairs airing cupboard (next to exterior wall). Anybody with any ideas on a rough cost to replace with a nice new combi?

    Greatly appreciated 🙂

  2. JustinNovember 1, 2016 at 7:58 pm #

    Who writes this crap? I suggest you do your homework. Thermostatic valves are NOT a requirement unless you are having a complete new system when you change a boiler. A full programmer is mandatory, a room thermostat is mandatory too. If the cylinder is of a certain age ( yellow lagged or NO lagging) then that’s supposed to be changed too

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