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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

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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Air Conditioning Running Costs UK 2026

10th April, 2026 Guides

Air Conditioning Running Costs...

Air conditioning running costs depend on how much electricity the unit uses, how long you...

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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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How to find a reliable air conditioning installer in the UK

10th April, 2026 Guides

How to find a reliable air con...

A reliable air conditioning installer in the UK should be qualified, well-reviewed, clear...

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Air Conditioning vs Fans: Which Is Better for UK Homes?

10th April, 2026 Comparisons

Air Conditioning vs Fans: Whic...

Air conditioning is better than a fan for most UK homes if you want proper cooling, better...

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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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Best Air Conditioning Brands

02nd April, 2026 Advice

Best Air Conditioning Brands

Find the best air conditioning brands in the UK for 2026, with a focus on performance, eff...

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Daikin Sensira Air Conditioning Unit Review

02nd April, 2026 Reviews

Daikin Sensira Air Conditionin...

The Daikin Sensira air conditioning unit boasts a blend of compact design with top-notch f...

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