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Stephen Day

Gas Safe Engineer at iHeat

Stephen Day is a Gas Safe registered and FGAS certified engineer with over 20 years of hands-on experience in the heating, cooling, and renewable energy industry, specialising in boiler installations, air conditioning, and heat pump systems.

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About Stephen Day

Stephen Day is a Gas Safe registered and FGAS certified engineer with over 20 years of hands-on experience in the heating, cooling and renewable energy industry.

Throughout his career, Stephen has designed, installed and maintained thousands of systems across homes and businesses in the UK. His background on the tools, combined with his directorship role at iHeat, gives him a rare understanding of both the technical and operational sides of the industry.

He has helped to secure Which? Trusted Trader accreditation all with a focus on delivering great service and long-term value for customers. He also writes for the iHeat blog, sharing practical advice and explaining heating topics in plain, helpful language.

Stephen continues to stay up to date with the latest heating technologies, building regulations and low-carbon innovations.

Gas Safe ID: 5910722

Expertise

  • Boiler systems and installation
  • Heat pumps and hybrid heating systems
  • Gas safety and compliance
  • System design
  • Renewable and low-carbon technologies
  • Technical training


Articles by Stephen Day are reviewed by iHeat’s technical team for accuracy and reliability.

Stephen Day's latest articles

AI Technology in Home Heating: The Future of Efficiency?

20th May, 2026 Guides

AI Technology in Home Heating:...

Artificial Intelligence (AI) is changing home heating by introducing smarter, more efficie...

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Worcester Bosch Boiler E9 Fault

10th April, 2026 Guides

Worcester Bosch Boiler E9 Faul...

E9 usually means your Worcester boiler has overheated or is struggling to move heat throug...

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Biasi Boiler Error Codes - How To Fix

10th April, 2026 Guides

Biasi Boiler Error Codes - How...

Some Biasi boiler error codes can clear with a reset, but others point to faults that need...

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Vaillant F72 Error Code - How To Fix

10th April, 2026 Guides

Vaillant F72 Error Code - How...

F72 usually points to a sensor fault or poor circulation in the heating system.

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Unusual Boiler Smells: Causes and Fixes

10th April, 2026 Guides

Unusual Boiler Smells: Causes...

Some boiler smells are harmless, but gas and burning smells need urgent attention.

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Boiler Ticking Noise

09th April, 2026 Guides

Boiler Ticking Noise

A ticking boiler is often caused by pipe expansion, a timer, or parts heating up and cooli...

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How Much Does Moving a Boiler Cost?

09th April, 2026 Guides

How Much Does Moving a Boiler...

Moving a boiler usually costs a few hundred pounds for a short move, but more complex relo...

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Baxi Boiler E133 Error Code

08th April, 2026 Guides

Baxi Boiler E133 Error Code

A Baxi E133 error usually means your boiler has failed to ignite because of a gas supply i...

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Back Boiler Replacement Cost in the UK

02nd April, 2026 Guides

Back Boiler Replacement Cost i...

Back boilers are outdated, inefficient, and pose safety risks. Upgrading to a combi boiler...

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How Much Does a Heat Pump Cost? 2026 Guide

27th March, 2026 Guides

How Much Does a Heat Pump Cost...

In the UK, a heat pump usually costs several thousand pounds, with most air source systems...

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Ideal F2 Error Code - How to Fix

27th March, 2026 Guides

Ideal F2 Error Code - How to F...

Ideal F2 usually means flame loss.

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Worcester Boiler Fault 227

27th March, 2026 Guides

Worcester Boiler Fault 227

Boiler systems utilise error codes as an internal diagnostic tool. They offer a swift indi...

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