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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

What is an Immersion Heater and What Does it Cost?

06th February, 2026 Advice

What is an Immersion Heater an...

Everything UK homeowners need to know about immersion heaters and running costs.

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How Old is My Boiler and When to Consider a Replacement?

06th February, 2026 Guides

How Old is My Boiler and When...

A modern, efficient boiler can operate at over 90% efficiency, leading to significant savi...

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Why Putting a Boiler Outside Is Often a Bad Idea

06th February, 2026 Guides

Why Putting a Boiler Outside I...

While putting a boiler outside may seem like a good idea to save space and reduce noise in...

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What is Boiler Frost Protection?

06th February, 2026 Guides

What is Boiler Frost Protectio...

Boiler frost protection is an important feature that helps prevent your boiler from freezi...

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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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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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Y Plan Wiring Diagram

05th February, 2026 Guides

Y Plan Wiring Diagram

A Y Plan heating system is a design used in some homes to manage both central heating and...

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Worcester Bosch Combi Boiler Hot Water Goes Cold

05th February, 2026 Guides

Worcester Bosch Combi Boiler H...

Ensuring consistent hot water supply in your Worcester Bosch combi boiler often necessitat...

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What Is a Combi Boiler?

05th February, 2026 Reviews

What Is a Combi Boiler?

Is a combi boiler worth it? Would your home benefit from a combi boiler? We will find out....

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Hot Water Tank Thermostat

05th February, 2026 Guides

Hot Water Tank Thermostat

For most UK homes, setting the hot water tank thermostat between 60°C and 65°C provides a...

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Boiler Repair Bolton

05th February, 2026 Guides

Boiler Repair Bolton

In Bolton, boiler repair costs and procedures vary significantly depending on the type of...

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Types Of Boiler

05th February, 2026 Guides

Types Of Boiler

The type of boiler that you choose can have some major impacts on your heating and hot wat...

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