This one common boiler mistake could end up costing you hundreds of pounds insurance experts have warned.

New data from Defaqto revealed that 94% of all boiler and home emergency insurance policies require you to have your boiler serviced before you can make a claim. This can be a fixed period prior to the breakdown, ranging from 12 months to 36 months, or can be simply stated as "in line with the manufacturer’s instructions".

Alongside this, the research revealed that just under half (46%) of policies will not cover a boiler over a certain age, According to the Defaqto data, the maximum age for a boiler is 15 years for 25% of policies, 14 years for 15% of policies, 10 years for 5% of policies and just nine years old for 1% of policies.

With households increasingly worried about the cost of living, experts are concerned that some moves to make short term savings could prove to be costly in the long run. Angela Pilley, home insurance expert at Defaqto, said: “We know that the cost of living is forcing people to make difficult decisions when it comes to prioritising their household budgets.

"The danger is that a short-term saving, by missing a boiler service or turning your heating off altogether, could be costly in the long run. It’s always important to check the terms and conditions of your insurance policy to avoid unwittingly invalidating your cover."

Specifically, Angela noted that some insurance policies also specify a limit on the boiler’s power output, with upper limits ranging from 75kw down to 44kw. According to Compare the Market, if you do not have insurance the cost to fix a boiler could roughly reach £500 however it could be even more. This is because the cost to fix a boiler will depend on a range of factors, including where you live, what kind of boiler you have and what the problem is.

Alongside this, Angela warns that your boiler breaking down could also impact your main home insurance policy too. As temperatures begin to fluctuate between freezing and thawing, burst pipes is a risk some homeowners face but a broken boiler might result in their home insurance claim potentially being declined.

She added: "It’s important to check the terms around how long you can leave your home unoccupied, especially during the winter months. Many have restrictions in cover or specific requirements around maintaining your heating at a minimum temperature if your home is left unoccupied for more than a specified period of time, typically 30 days or more.

“A small number of providers are now introducing additional terms for escape of water claims which apply during the winter months. This relates specifically to maintaining your heating above a minimum level even if you are only going to be away for a short period of time, for example, three to seven days. Some are even applying a minimum heating requirement when you are occupying the property.”

How to avoid costly call out and repair bills this winter

The insurance experts at Defaqto have shared several ways you can avoid an unexpected costly bill.

  • Always check the terms and conditions of your insurance policies - for boiler and home emergency cover look out for boiler servicing requirements, age limits and upper limits on power output
  • If you plan to leave your home unoccupied then check if you are required to maintain your heating at a minimum temperature during the time you are away and if this is required then set your heating to this 24/7 whilst you are away
  • If you have a smart thermostat, most will have an anti-frost setting to keep your home heated to a very minimal temperature that will stop pipes from freezing
  • If you do not have a smart thermostat, most radiators will have a setting with a snowflake symbol – turn to this setting to allow minimal water flow between pipes and radiators to prevent freezing - you should also consider setting the heating on a timer if you are going away
  • If the heating system is powered by an electric boiler, solar or solid fuel, check that your boiler or home emergency policy will cover this
  • When changing the boiler remember to check that your existing boiler or home emergency policy will cover it
  • If the boiler has been purchased within the last few years, it’s worth checking what cover the manufacturer gives as standard under the warranty - but also check for any exclusions