Stephen Day profile photo

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.

LinkedIn

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

Pressure Dropping on Boiler Every Day

30th September, 2026 Guides

Pressure Dropping on Boiler Ev...

Boiler pressure is the measure of balance between water and air within the central heating...

read article arrow Read Article
What Is An Expansion Vessel?

30th September, 2026 Guides

What Is An Expansion Vessel?

An expansion vessel is an essential component of a modern boiler system, serving a pivotal...

read article arrow Read Article
No Water Coming Out Of Hot Tap (Combi Boiler)

30th September, 2026 Guides

No Water Coming Out Of Hot Tap...

Addressing the lack of hot water from a tap usually starts with understanding how a combi...

read article arrow Read Article
What temperature should my boiler be set at for central heating?

30th September, 2026 Guides

What temperature should my boi...

Boilers are the heartbeat of a home's central heating system, efficiently managing the bal...

read article arrow Read Article
Types Of Boiler

30th September, 2026 Guides

Types Of Boiler

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

read article arrow Read Article
Boiler Pressure Too High: What It Means and How to Fix It

30th September, 2026 Advice

Boiler Pressure Too High: What...

High boiler pressure is usually anything above 2.5 bar on the pressure gauge when the heat...

read article arrow Read Article
Potterton boiler E119 error code: what it means and what to do

29th September, 2026 Guides

Potterton boiler E119 error co...

The Potterton E119 error code indicates low system pressure. Check the pressure gauge firs...

read article arrow Read Article
Heat Pump Pros and Cons - A Complete Guide for UK 2026

29th September, 2026 Comparisons

Heat Pump Pros and Cons - A Co...

As one of the hottest topics in the industry, heat pumps are being contemplated by homeown...

read article arrow Read Article
Heat Pumps: The Ultimate UK guide

29th September, 2026 Guides

Heat Pumps: The Ultimate UK gu...

As energy efficiency and environmental concerns continue to shape our choices, heat pumps...

read article arrow Read Article
How Much Does a Heat Pump Cost? 2026 Guide

29th September, 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...

read article arrow Read Article
Tips to Look After Your Heat Pump in Winter

29th September, 2026 Guides

Tips to Look After Your Heat P...

Heat pumps are an efficient and eco-friendly way to heat your home, but they can face chal...

read article arrow Read Article
Air Source Heating - Air to Air Source Heat Pump

29th September, 2026 Guides

Air Source Heating - Air to Ai...

Air source heating harnesses environmental warmth to heat homes efficiently, utilizing a d...

read article arrow Read Article