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Water from your combi boiler too hot to handle? Here's what to do

Us brits love to moan about the temperature; too hot, too cold, too wet. There's no pleasing some, but if you're genuinely fuming with the temps that your boiler is gifting you with, here's what it might be and how you can fix it.

If your face has recently been melted off by water carrying the power of a thousand suns and you're reading this through squinted eyelids, freshly decorated with third degree burns, then you might want to turn the temperature down on your boiler.

However, it could be fault requiring the attention of a heating engineer. Below are common causes of a combi boiler producing water that's too hot.

If your boiler is old and in-efficient, you should probably consider a replacement. We fit boilers UK-wide from just £1,595 - get your fixed price online.

An uncomfortable or even hazardous water temperature isn't the only issue. Over-heating water could also cause boiler kettling which will require professional attention.

Temperature dials on the boiler unit are too high. There may be two - one for hot water and one for central heating

Reduce the temperature to between 40-50 degrees Celcius. If the problem persists, you'll need to call an expert

Cost IconCost to fix:

Problem still present? Get a fixed price replacement, online.

Faulty thermostat

You'll need a qualified Gas Safe engineer to repair or replace the thermostat

Cost IconCost to fix:
£100  £200

Problem still present? Get a fixed price replacement, online.

Got an ageing Worcester combi boiler? It can be common for them to produce water that's too hot due to a number of issues. Fortunately, Worcester's usually come with long warranties, so it's worth checking if yours is still covered before paying for repair work.

Flow rate. If the flow rate isn't suitable (too slow), it may be causing the flowing water to heat up more than it should

We'd reccommend having a qualified heating engineer take a look at the boiler

Cost IconRepair cost:
£50 (+Callout fee!)

Problem still present? Get a fixed price replacement, online.

Top tip: In the meantime, use the cold tap.

The common boiler issues which are causing your water to get too hot can often be repaired by heating engineers for small fees but if you have a particularly old boiler and the repair cost is upward of £300, then it's certainly worth looking into the cost of replacing your boiler, as they're much more prone to future breakdowns. The savings on your energy bill might just mean it'll pay for itself. Paying for a new boiler entirely in cash can be a painful sting to the wallet but pay monthly boilers are becoming ever more popular.

How to get the best deal on a combi boiler

Without boasting, buy from us.

We're an online, nationwide boiler installation business with 600+ 5 star reviews from a shed load of happy customers.

Because we're online, our overheads are low which means we pass those savings on to our customers, ensuring they're always getting the best deal on a new combi boiler. Plus, because of the volumes that we install, we're able to access exclusive warranty lengths from our partner manufacturers. For example, we can offer 10 years of protection on the Viessmann 050 range, whereas your traditional installer can only offer you 7. Boom.

Plus, all of our combi boiler installations come with upgraded wireless controls, a Fernox TF1 omega boiler filter and powerful chemical protection.

To get the best deal on a new combi boiler, answer some quick online questions and we'll give you an instant fixed price.

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Heatable is registered in England and Wales No. 08804726 (VAT No. GB205805920 ). Trading address is 1 Station Road, Great Sankey, Warrington, Cheshire, WA5 1RH. Heatable acts as a credit broker (not as a lender) and offers credit products through a panel of lenders. Heatable is authorised and regulated by the Financial Conduct Authority (reference no. 805259).

[1] Price based on a like for like combi swap in a 2 bed, 1 bathroom terraced home with a standard flue

[*] Installation dates are subject to installer availability

[¹] only available on combi boiler installations