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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

Vaillant F72 Error Code - How To Fix

06th February, 2026 Guides

Vaillant F72 Error Code - How...

If you're experiencing the Vaillant F72 error code on your boiler, our guide can help. We...

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How to increase boiler efficiency

06th February, 2026 Guides

How to increase boiler efficie...

Want to maximise your boiler efficiency in cold weather? Our guide provides tips on how to...

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Ideal F2 Error Code - How to Fix

06th February, 2026 Guides

Ideal F2 Error Code - How to F...

If you're experiencing the Ideal F2 error code on your boiler, our guide can help. We expl...

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How to Fix Boiler Airlock: Expert Guide

06th February, 2026 Guides

How to Fix Boiler Airlock: Exp...

If you're struggling with a boiler airlock, our comprehensive guide can help. We explain t...

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Disadvantages of Oil Boilers: Exploring Key Concerns

06th February, 2026 Guides

Disadvantages of Oil Boilers:...

Oil boilers may be a popular choice for home heating, but they come with some significant...

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Best Boiler for Terraced House

06th February, 2026 Guides

Best Boiler for Terraced House

Searching for the best boiler brand for terraced housing? Our guide compares the top-rated...

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Can I Have Air Conditioning and a Gas Boiler?

06th February, 2026 Guides

Can I Have Air Conditioning an...

Achieve year-round comfort in your boiler-heated home by integrating efficient air conditi...

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How to Link a Wood Burner to Your Central Heating (UK Guide)

06th February, 2026 Guides

How to Link a Wood Burner to Y...

Connecting a wood burner to your central heating system can be an efficient way to heat yo...

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When Does a New Boiler Need Its First Service?

06th February, 2026 Advice

When Does a New Boiler Need It...

Having your boiler serviced regularly is important for ensuring its safety and efficiency,...

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Vaillant Combi Boiler Costs

06th February, 2026 Guides

Vaillant Combi Boiler Costs

As Vaillant continues to innovate, integrating smart technology and improving energy perfo...

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What is a Heat Exchanger?

06th February, 2026 Guides

What is a Heat Exchanger?

Heat exchangers are pivotal devices within a boiler system, playing a crucial role in tran...

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Flashing Radiator Symbol on Boiler

05th February, 2026 Guides

Flashing Radiator Symbol on Bo...

Recognising a flashing radiator symbol on a boiler's display is pivotal for maintaining ef...

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