Central heating installation and upgrades
Whole systems, or the parts that make the heating work better.
From a full new system in a house that has never had one, to swapping a cold radiator or fitting smart controls, our engineers make central heating work properly in every room.
Small upgrades, warmer rooms
Cold spots and slow-to-heat radiators are often down to sludge in the system. A power flush and a magnetic filter can bring an old system back to life.
Bigger or better-placed radiators let the boiler run cooler and more efficiently, and get a home ready for a heat pump later.
Smart thermostats and good valves give you control room by room.
- A power flush on a five-radiator system typically costs £300 to £750 (Which?).
- Unvented cylinders must be fitted by an engineer qualified for unvented hot water work (Approved Document G).
- A magnetic filter catches sludge before it reaches the boiler and is a common warranty condition.
Which upgrade fixes which problem?
| Problem | Usual fix | Find out more |
|---|---|---|
| Radiators cold at the bottom | Power flush and a magnetic filter | Power flushing |
| Some rooms never warm up | Bigger or better-placed radiators, TRVs | Radiators and TRVs |
| Weak showers with 2+ bathrooms | Unvented hot water cylinder | Hot water cylinders |
| Heating on when nobody is home | Smart thermostat and zoning | Smart thermostats |
| Cold floors in an extension | Underfloor heating | Underfloor heating |
What a full central heating installation includes
A new central heating system has a few main parts, and each one has to be sized to the house. Get one wrong and the rest of the system pays for it.
- A heat source: a gas boiler, an oil boiler or a heat pump
- Heat emitters: radiators in each room, or underfloor heating on the ground floor or in an extension
- Pipework: run under floors and through walls to every radiator, sized for the flow each room needs
- Hot water: straight from a combi boiler, or a vented or unvented cylinder with a system boiler or heat pump
- Heating controls: a programmer or smart thermostat, plus thermostatic radiator valves for room-by-room control
Choosing the right heat source
A boiler is one part of a central heating system, not the whole thing, and the type of boiler or heat pump you choose shapes everything else.
On mains gas, gas central heating with a combi boiler suits smaller homes with one bathroom, while a system boiler and cylinder suits busier homes. Our boiler installation page compares the options.
Off the gas grid, an oil boiler or LPG works, or you could skip fossil fuels and fit a heat pump with help from the Boiler Upgrade Scheme, currently £7,500 in England and Wales. A heat pump needs larger radiators or underfloor heating, so it is far easier to plan for at the start of a new installation than to retrofit later.
The installation process
Installing central heating from scratch is a bigger job than a boiler replacement, and it helps to know what is coming.
- Survey and heat loss: we measure each room and work out its heating requirements, so radiators are sized properly rather than guessed
- Design: we choose the right boiler or heat pump, plan pipe routes and radiator positions, and agree where the controls go
- First fix: floorboards come up and pipework goes in, along with brackets and valves for each radiator
- Second fix: radiators, the boiler or heat pump, the cylinder and the controls are fitted and connected
- Commissioning: a Gas Safe registered engineer (OFTEC or MCS certified for oil and heat pumps) fills and cleans the system, adds inhibitor, then tests and balances it so every radiator heats evenly
Central heating installation costs
There is no honest single price for a full central heating installation, because property size, the number of radiators, pipe runs, floor types and labour cost vary so much. What we can give you are the market figures for the parts of the job that Which? tracks.
- A new boiler, fully installed: around £1,400 to £7,000 (Which?)
- Adding a vented cylinder: £350 to £750; an unvented cylinder: £900 to £1,400 (Which?)
- Power flushing an existing five-radiator system: £300 to £750 (Which?)
- Market figures, not Wisp prices: you get one fixed central heating installation cost after a free survey, with finance available on new boilers and heat pumps
Upgrading the system you already have
Not every home needs a new central heating system. In plenty of older heating systems the boiler is fine and the problem is sludge, undersized radiators or poor heating controls, and fixing those is quicker and cheaper than a full replacement.
Balancing is one of the simplest fixes. Each radiator has a lockshield valve that sets how much hot water it gets; if they are all wide open, the radiators nearest the boiler hog the flow and the far rooms stay cold. Setting them properly is part of every system we commission.
Running costs and energy bills come down when the boiler can run cooler, the system is clean and you only heat the rooms you use. A smart thermostat with zoning makes that easy.
What we do
Radiators and TRVs
Warmer rooms, better control, and radiators that suit the space.
Find out moreUnderfloor heating
Even warmth from the floor up, and no radiators on the walls.
Find out morePower flushing
Clears the sludge so your radiators and boiler can work properly.
Find out moreMagnetic filter fitting
A small cylinder on a pipe that saves your boiler a lot of grief.
Find out moreHot water cylinders
Vented or unvented, sized for how your household uses hot water.
Find out moreSmart thermostats and controls
Run your heating from your phone and stop heating an empty house.
Find out moreFrom first question to signed off
Tell us the problem
Cold rooms, noisy pipes, or starting from scratch.
Survey
We check the system and measure the rooms.
Fixed quote and install
A clear price and tidy work.
What is included
- Full system design and installation
- Radiators, valves and pipework
- Underfloor heating
- Vented and unvented hot water cylinders
- Power flushing and filters
- Smart controls
Central heating FAQs
Can you install central heating in a house that has never had it?
Yes. We design the system from scratch, including the boiler or heat pump, radiators, pipework and controls.
Do you fit unvented cylinders?
Yes, by G3 qualified engineers. See hot water cylinders.
Is underfloor heating worth it?
It works well in extensions and on ground floors, especially with a heat pump. See underfloor heating.
Which smart thermostats do you fit?
Hive, Nest, Tado and Drayton Wiser, among others.
How much does it cost to get central heating installed?
It depends on the size of the house, the number of radiators and the heat source. Which? puts a new boiler alone at around £1,400 to £7,000 fitted, and the pipework, radiators and controls come on top. We give you one fixed price after a free survey.
What is the most efficient home heating system?
For most homes, a well-designed heat pump, because it delivers more heat than the electricity it uses. Among fossil fuel systems, a modern condensing boiler on a clean, balanced system with good controls is the most efficient. The best choice depends on your insulation and fuel supply.
Can a central heating system lose pressure without a leak?
Yes, sometimes. Bleeding radiators lets air out and drops the pressure, and a failing pressure relief valve or a flat expansion vessel can make it fall too. If you top up and it keeps dropping, get an engineer to look before it damages the boiler.
Read before you decide
Combi vs system vs regular boiler: which one suits your home?
The right boiler type comes down to how much hot water you use at once and what your home already has. Here is how to work it out.
Read the guideWhat size boiler do I need?
Boiler size is measured in kilowatts (kW), and bigger is not better. Here is how to get a ballpark figure, and why a proper heat loss check beats any rule of thumb.
Read the guideReady to talk about central heating?
Answer a few questions and we will come back with a free, fixed quote.