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How much does it cost to buy a new boiler?

We received wildly different quotes for installing exactly the same boiler

Young woman reading heating oil quotes

A snapshot Which? investigation has revealed a staggering difference in quotes for installing a new boiler.

You turn on your ailing boiler on a cold winter’s morning and discover that it’s finally given up the ghost. The tempting thing to do is to call out the first available boiler engineer. But that could turn out to be a very costly mistake, as our exclusive research reveals.

The quotes we received for the same type of boiler, being installed in the same location, varied by as much as £3,200. One quote came in at a suspiciously low £1,500, and another at an eye-watering £4,764.

Our investigation suggests that you don’t necessarily need to pay more to get the very best boiler. The quotes we received for three Best Buy boiler brands were no higher than quotes for brands that get middling scores in our boiler brand reviews.

If you need a new boiler, make sure you get one that will last by picking from one of the best boiler brands.

How much is a new boiler?

The median price of the ten quotes was £2,595, with one as low as £1,500 and one as high as £4,764.

Our expert ultimately ended up replacing a regular non-condensing boiler with a modern condensing boiler for less than £2,500.

We had expected that the brands performing less well in our boiler surveys would be cheaper than the Best Buy brands, but this wasn’t the case. In fact, the cheaper unit cost of some boiler brands was not reflected in the final quotes.

As well as wildly differing quotes, we were also offered conflicting advice. Some claimed the existing pipework needed to be replaced and others said it was fine.

And there were also differences in how long each engineer spent in the house costing up the job. One could hardly wait to leave, while others spent more than an hour.

If an engineer is in and out in a flash and sends a rushed quote that isn’t itemised, such as the engineer who quoted £1,500 in our research, we wouldn’t recommend you trust them with the work.

Our research

When our boiler expert needed to replace his own boiler he took the opportunity to put heating engineers to the test. He asked 10 installers to quote for the same work: to replace a non-condensing regular boiler with a modern regular condensing boiler in the same location. He also asked for quotes to include 10 thermostatic radiator valves, a full chemical power flush, system balancing, MagnaClean filter, a new circulation pump and a new cylinder thermostat.

All of the quotes were received in the same week, taken from engineers who install boilers from boiler manufacturers that top our boiler surveys, along with mid-tier brands.

Five tips for getting the best price

Several heating engineers mentioned to our expert that the summer is a good time to get a new boiler. Heating engineers are typically less busy in the summer, so you’re more likely to receive a competitive quote.

We know that most of you will only replace a boiler when your old one breaks, most likely during winter, so here are our top tips for making sure you get the best price:

  • Get at least three quotes. Our expert got 10 but three quotes should be enough to reveal any that are unnecessarily high. Tell the engineers you are getting more than one quote, too, so they know to price the job competitively.
  • Ask for the quote to be fully itemised, including the cost of the boiler, the cost of labour, and the cost of any extra parts. You can only compare quotes fairly and accurately if they’re properly itemised.
  • Ask for the system to be cleaned before installation and balanced afterwards. This is essential for the ongoing reliability and efficiency of your new boiler.
  • A good engineer will take up to an hour to properly survey your home. If they cut corners at the survey stage, it shouldn’t fill you with confidence about the eventual workmanship.
  • Before the engineer arrives, read our tips on how to get the best boiler installation and compare the pros and cons of combi, heat-only and system boilers.

If you’re replacing your boiler, make sure you check our boiler installation costs page that details how much you should expect to pay for each type of new boiler.

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