London's
Premier
Heating
Engineers
Installing boilers, hot water cylinders, underfloor heating, heat pumps & air conditioning across London & surrounding areas - from a first flat to a multi-million pound home renovation, always to the same standard.
220+ five-star Google reviewsPremium installations.
Across London.
We specialise in boiler, cylinder, heat pump, underfloor heating and air conditioning installations across London — carried out to the highest standard by a Gas Safe registered, F Gas qualified team. With commercial as well as domestic registration, we also take on what many domestic firms can't: commercial boilers for larger homes and commercial-grade gas kitchen installations.
Installer for
F-Gas registered for air conditioning & refrigerant work — verify on the REFCOM register.
Coverage across
London & beyond.
We travel for installation work, across all of London and the surrounding areas, from Chelsea to Hornchurch, St Albans, Maidenhead and Camberley.
We are on the doorstep of Acton, Chiswick, Ealing, Hammersmith, Harrow, Hounslow, Shepherd's Bush, Southall, Uxbridge and Wembley.
Boiler servicing, repairs, gas safety certificates and emergency callouts across West, North West and South West London.
220+ five-star
Google reviews.
Most of our customers have been with us for years — and bring their families along too.
"Ravinder Singh provided the best customer service we've ever experienced. Professional, punctual, and genuinely caring — he went above and beyond to ensure everything was perfect on a new boiler install. Truly outstanding work!"
"I have had a heating system including a Vaillant boiler, Megaflo and underfloor heating installed by DGN GAS. A very professional service and am extremely happy. I especially like the after sales care. Would highly recommend."
"Absolutely wonderful service. 100% reliable, transparent and competitive. A company you can trust and feel in safe hands with."
"I had a new hot water cylinder fitted. DGN GAS arrived the next day, carried out diagnostics and resolved the problem. Everything came to a very fair price. I would highly recommend DGN for all my plumbing needs."
"Have used DGN GAS a few times now. They installed a boiler at my parent's house and do the annual boiler servicing. I had a boiler and underfloor heating installed at my house too. Very happy with everything."
"DGN Gas installed a new Baxi Boiler for me in February 2021, they have serviced and carried out the landlord gas safety inspections ever since. Excellent professional service. Extremely satisfied."
The name in those reviews.
That's Ravinder Singh, who founded DGN GAS and has spent almost a decade building it one job at a time.
The principle hasn't changed since the first install: every home gets the same standard — from a multi-million pound property to a first flat. English, Punjabi and Hindi spoken.
More about DGN GAS ›Every home.
One standard.
The same standard, regardless of postcode
From prestigious multi-million pound renovations to a family's first home — the property changes, the standard doesn't.
Peace of mind for families
For families who simply want heating they can rely on — properly installed, fully certified, with someone real at the end of the phone.
Industry recognised credentials
Gas Safe registered for both domestic and commercial work. Baxi Approved, Vaillant Advance, Worcester Bosch Installers, and featured in the Megaflo installer campaign.
Customers who stay — and bring their families
Most of our customers have been with us for years. They send their parents, their children, their tenants.
Frequently asked
questions.
Are you Gas Safe registered?
Which areas do you cover?
Are you accredited by the manufacturers?
Why choose DGN GAS?
How much does a new boiler cost in London?
Do you service air conditioning?
Your questions,
answered straight.
What does a boiler installation involve?
A boiler installation is a survey, a written fixed-price quote, the install itself, commissioning, and registration of the manufacturer guarantee. We install all major brands across London and the surrounding areas, from a first flat to a multi-million pound renovation, always to the same standard.
How much does a new boiler cost in London?
It depends on four things: the size of boiler your home needs, whether you are staying with a combi or moving to a cylinder system, where the flue can run, and whether the system water needs a powerflush first. As a rough guide, a combi boiler installation usually comes in between £2,500 and £4,500, and a system boiler with a cylinder is a bigger job - approximately £7,000 to £8,000 - but both can vary with the job, the brands and models used, and other factors. The full breakdown is in our new boiler cost guide, and every DGN quote is a written fixed price after a survey, so the number you are given is the number you pay.
Combi or cylinder - which suits your home?
A combi suits flats and smaller to medium size homes; a cylinder with a system boiler suits homes where more than one shower or bath runs at once - especially larger homes that have the space for the cylinder. A combi is only designed to supply one hot water tap at a time - that is its honest limit. We install both, and we will tell you at the survey which your home actually needs.
| Combi boiler | System boiler + cylinder (e.g. Megaflo) | |
|---|---|---|
| Hot water | Heated on demand | Stored, ready to go |
| Two showers at once | Struggles | Handles it |
| Space needed | Boiler only | Boiler + cylinder |
| Best for | Flats, smaller and medium homes | More than one shower or bath running at once |
| Typical install | Usually a straight swap | More pipework, longer install |
How long does an installation take?
A straightforward combi-to-combi swap usually takes a day and a half - where we can, we put an extra pair of hands on site to get it done in a day and keep the inconvenience to the household down. A boiler and cylinder installation is usually two to four days - sometimes less, occasionally more, depending on the job. You will be given the timing in writing with the quote.
Who is allowed to install a boiler?
In the UK it is illegal to install a gas boiler unless it is done by a qualified Gas Safe registered engineer, or by someone working under the supervision of one. DGN GAS is Gas Safe registered No. 623092 for both domestic and commercial gas work, and you can check the registration on the Gas Safe Register before we set foot in your home.
Should a 20-year-old boiler be replaced?
Usually yes, but not always immediately. A boiler that old is well past its design life, parts become hard to source, and a modern condensing boiler uses noticeably less gas. Worth knowing: modern condensing boilers have a life span of about 10 years, so once a boiler starts giving repeated trouble it is often better value to change it than to keep spending on repairs. If yours is still running safely, the sensible step is an honest assessment - ask us any time, or have it looked at during its annual service - rather than a panic replacement. We will tell you which side of the line yours sits on.
A local installer or British Gas?
The same boilers, the same manufacturer guarantees - through our Vaillant, Baxi, Worcester Bosch and ATAG installer status you get the extended manufacturer guarantee either way. The difference with DGN is the relationship: you can speak directly to Ravinder, the founder whose name is on the reviews - most of our customers have been with us for years - with servicing from the same team afterwards in West, North West and South West London.
Do I qualify for a boiler grant?
Government help exists but it is scheme-specific. We install heat pumps under the Boiler Upgrade Scheme, which gives up to £7,500 towards the cost. We do not install boilers under grant schemes - those run through energy suppliers and councils for qualifying households, the rules are strict, and most people do not qualify. Ask us and we will give you our honest guidance.
Boiler servicing in West, North West and South West London
An annual service keeps the manufacturer guarantee valid and can often catch or head off faults early - before winter, when you least want one. We service, repair and certify boilers across West, North West and South West London - book before the cold snap, not during it.
Ready to talk?
Get in touch today.
Whether it's a new installation, a service or an emergency — honest advice and a no-obligation quote.
Get a Quote 07813 474638 WhatsApp UsPage last updated: September 2026