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1 October 2020

Glow-worm Boiler Guide

Find out how Glow-worm boilers fared in our latest boiler reliability survey, and what trusted boiler engineers make of Glow-worm.
Matthew Knight

British boiler brand Glow-worm has more than 75 years of experience in the heating business and says it is committed to 'top quality, reliability and exceptional durability'.

Glow-worm has several different gas combi boiler ranges, including Glow-worm Ultimate boilers, Glow-worm Betacom boilers, Glow-worm Easicom, Glow-worm Essential boilers and Glow-worm Energy boilers. Glow-worms ranges encompass all different types and sizes of boilers including combi boilers, system boilers and regular heat-only boilers.

You can find more details about the individual products in these ranges in our Glow-worm boiler reviews.

More than 7,000 members of the general public take part in our annual boiler brand reliability and customer satisfaction survey, enabling us guide you to the best and worst boiler brands. We also conduct a survey with more than 150 trusted boiler engineers to get their independent views on which boiler brands are the best.

Which? verdict on Glow-worm boilers

Here, you'll find out how reliable Glow-worm boilers are, and what Glow-worm owners think about their boiler. We also reveal what trusted heating engineers think of Glow-worm boilers' build quality, and much more.

Which? members can log in to view what owners and engineers make of Glow-worm in the table below. If you're not already a member, sign up for a £1 trial to Which? for one month.

Boiler brand guide
Brand data for Glow-worm boilers
Overall score M
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Customer score
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Engineer recommendation
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Build quality
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Availability of parts and spares
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Ease of fixing a common fault
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Ease of servicing
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Table notes

The reliability and customer score are based on responses from a May and June 2020 survey of 7,500 boiler owners.

Engineer recommendation, build quality, availability of parts and spares, and ease of fixing a common fault and ease of servicing are based on responses to a June 2020 survey of 153 Which? Trusted Traders heating engineers.

How much do Glow-worm boilers cost?

Glow-worm boilers cost between £640 and £1,520, depending on the type and size of boiler. 

Choosing the best Glow-worm boiler

The number of years included on the standard Glow-worm warranty varies by boiler range. For warranty protection, either complete and return the warranty form that comes with the box or fill in the warranty form online.

Glow-worm will provide extended warranty packages that last between three and five years.

Glow-worm extended warranties

01773 824639

Glow-worm repairs and spares

Glow-worm has its own team of 200 Gas Safe registered service engineers. 

Boiler breakdown cover is also available from Glow-worm, and there are three levels of cover available.

Boiler breakdown cover quotes

0800 032 7340

Glow-worm spare parts

01773 596020

Glow-worm contact details

You can contact Glow-worm by writing to:


Nottingham Road,

Belper, Derbyshire.

DE56 1JT

or through its website (glow-wormheating.co.uk).

Glow-worm customer service

01773 828 100

Glow-worm technical enquiries

01773 828 300