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Installing and servicing boilers in South East England

At Diamond Gas & Heating, the customer is at the heart of everything we do. We are a family-run business with specialist Worcester Bosch Accredited, Gas Safe registered installers. We offer top-quality boiler services, repairs and installations to Portsmouth, Fareham, Gosport, Southampton and all surrounding areas.

Our Services

We are a Worcester Bosch Accredited Installer

With that come great benefits to you

  • Up to 12 years guarantee on Worcester Bosch gas boilers***
  • All installs include a system filter and inline scale filter
  • Our engineers are Worcester trained
  • Finance options available
  • All premium options include a smart thermostat

How much a new boiler could cost you? It’s less than you think.

Start your boiler quote

Choose how you want to finance your boiler

Includes a new top of the range Worcester Bosch boiler, controls and installation

Yours and fitted from* 1,695 Includes VAT
  • From 2 - 10 years finance options
  • 0% APR spread the cost with 24 equal monthly payments interest free
Find out how finance could help you

Reassurance from just
£7.50 per month

When it comes to boilers and central heating, peace of mind is the most important thing we can offer. That’s why our four-tiered care plan system is great. It means you can rest easy knowing you’ll be looked after when you need it most.

Why choose
Diamond Gas and Heating?

  • Quality-rated boilers

    All of our boilers come with a manufacturer-backed guarantee and are Which? Best-Buy rated.

  • Honest and accurate pricing

    We provide fast and accurate quotations with no hidden fees or costs.

  • Warmcare packages

    We offer flexible and scalable packages to suit your needs, ensuring you feel safe and secure in the knowledge that you are protected from boiler breakages and shutdowns.

  • Friendly professional service

    All of our engineers are Gas Safe registered and follow strict practice guidelines.

A family business

When husband and wife Ian and Louise Simm launched Diamond Gas & Heating in 2011, they knew they could offer something better than the local competition.

The pair had military backgrounds, each serving in the Royal Navy, with a combined service of 28 years. Ian had been an engineer and Louise in communications.

With their combined skills and background, the team knew they could offer the competitive prices of a local gas fitter, without compromising on quality and customer service –  all while offering 24/7 call-outs and complete peace of mind for the customer – something that truly sets them apart from the rest.

Ian Simm


Louise Simm

Find out More