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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

Glow-Worm F29 Error Code - How To Fix

20th May, 2026 Guides

Glow-Worm F29 Error Code - How...

The Glow-Worm F29 error code indicates a loss of flame during operation, which can cause a...

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Glow Worm F1 Fault

20th May, 2026 Guides

Glow Worm F1 Fault

Boiler error codes are critical indicators for diagnosing heating system issues. They serv...

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Glow Worm Combi Boiler Costs

20th May, 2026 Guides

Glow Worm Combi Boiler Costs

A combi boiler, or combination boiler, is a high-efficiency water heater and a central hea...

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Glow Worm Boiler Review: Ultimate₃ Combi

20th May, 2026 Reviews

Glow Worm Boiler Review: Ultim...

Combi boilers, or combination boilers, epitomise efficiency and convenience in modern home...

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Glow Worm Boiler Not Firing Up No Fault Code

20th May, 2026 Guides

Glow Worm Boiler Not Firing Up...

Boiler error codes are a critical feature intended to assist in the diagnosis of issues wi...

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Difference Between LPG and Natural Gas

20th May, 2026 Advice

Difference Between LPG and Nat...

In this article, we’re going to be explaining some ways in which you can identify whether...

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Free Boiler Scheme/Grants 2026 - UPDATED

20th May, 2026 Guides

Free Boiler Scheme/Grants 2026...

Navigating the landscape of grants can be complex, with schemes differing in their eligibi...

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Flashing Radiator Symbol on Boiler

20th May, 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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Understanding Your Boiler Settings & Controls Explained

20th May, 2026 Guides

Understanding Your Boiler Sett...

Boiler settings play a crucial role in the performance and efficiency of your heating syst...

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ESI Thermostat Troubleshooting UK

20th May, 2026 Guides

ESI Thermostat Troubleshooting...

ESI thermostats are designed to help maintain a comfortable temperature in homes and offic...

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EPH Combi Pack 4 Thermostat

20th May, 2026 Reviews

EPH Combi Pack 4 Thermostat

A modern and capable thermostat can often be overlooked as a key tool, synchronising with...

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Energy Saving With Your Boiler

20th May, 2026 Advice

Energy Saving With Your Boiler

For most homes in the UK, the cost of heating and hot water can be very pricey. That's why...

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