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The Most Common Boiler Faults

By Matthew Knight

Which? reveals the most common problems with condensing gas and oil boilers, according to our boiler owners' survey.

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In May 2016, we asked Which? members about the faults and annoyances they had experienced with their condensing gas and oil boilers they'd installed within the previous six years. 

A quarter of them had experienced some kind of fault with their gas or oil boiler since they had bought it. Luckily, not all faults needed a professional repair. However, the average cost of repairs was £188.
The most common boiler faults
Fault Gas boilers Oil boilers
9% 8%
5% 4%
5% 3%
4% 0%
4% 4%
4% 2%
3% 4%
4% 2%
2% 4%

Table notes
1 The most common faults are based on responses from a survey of 10,779 members of Which? Connect panel members about their boilers that took place in May 2015.


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