Boiler installation: conversions, moves and flushing
Boiler installation is more than swapping one boiler for another. Changing the type of boiler, replacing a back boiler, moving the boiler or flushing the system all add pipework, days and cost. Here is what each typically costs.
- Boiler conversionsA boiler conversion replaces a system or regular boiler with a gas combi, which usually means taking out the hot water cylinder and the loft tanks and re-plumbing the system.from £2,800typically £3,600System or regular boiler to gas combi, fitted
- Back boiler replacementBack boiler replacement starts with a boiler that sits behind a gas fire in the fireplace.from £3,000typically £4,400Back boiler to gas combi, fitted
- Boiler relocationBoiler relocation means moving the boiler, with new pipework, a new flue route and sometimes a new condensate drain.from £400typically £800Moving a boiler to a new position in the home
- Power flushingPower flushing pushes water through the radiators and pipework at speed to clear sludge and rust.from £350typically £500Power flush of a central heating system
How to choose a boiler installation job
The cheapest installation is a like-for-like swap, which is covered on our boiler types pages. This section covers the jobs that add to it: converting a system or regular boiler to a combi, replacing a back boiler, moving the boiler to a new position and power flushing the system before a new boiler goes on.
Often these are done together. Moving a boiler is cheaper when the engineer is already fitting a new one, and a power flush belongs before a new boiler goes on, not after it.
What to compare across boiler installation quotes
- What is included. Check the quote covers removing the old boiler, new pipework, the flue, a magnetic filter and making good. Anything missing is a later bill.
- The days. A conversion or a back boiler replacement takes longer than a swap, and the heating is off for part of it. Ask how many days.
- The system. An old system may need a flush or new valves before a new boiler goes on under warranty. Ask what the installer found when they tested the water.
- The boiler. A new boiler is part of the job. See combi boiler prices and our boiler types page for what each type costs fitted.
Get quotes for your home
A guide price only takes you so far. Local firms can price the work on your own home, and comparing a few quotes is the quickest way to see what is reasonable.
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