Megaflo Installation
in London
Megaflo and unvented hot water cylinders supplied and fitted across London and the surrounding areas by our G3-qualified team. Megaflo is part of the Baxi group, and we are a Baxi Approved Installer.
"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."
Unvented cylinder specialists
Recognised by Megaflo
themselves
Featured in the Megaflo Installer Campaign
Megaflo is the UK's leading unvented cylinder brand — part of the Baxi group. DGN GAS was selected to feature in their own installer campaign. This reflects the standard of our cylinder installation work across London.
Hot water that never
runs out
A modern unvented hot water cylinder transforms the hot water experience in your home. Unlike a combi boiler, a cylinder stores a large volume of hot water — delivering powerful mains-pressure hot water to every tap and shower simultaneously.
It's the preferred choice for larger homes, homes with multiple bathrooms, or any household where hot water demand is high.
Which cylinder is
right for you?
Unvented Cylinder
Connected directly to the mains. Delivers hot water at mains pressure — powerful showers, fast-filling baths, multiple outlets simultaneously. No loft tank needed. Megaflo is the market leader.
Vented Cylinder
Works with a cold water storage tank in the loft. Reliable and cost-effective — often the right choice for older properties with gravity-fed systems.
Heat Pump Cylinder
Designed to work with air source heat pumps. If you're moving away from gas, a heat pump cylinder is an essential part of the system.
Not Sure?
Call us to discuss your options — we'll advise based on your property, existing setup and hot water needs.
Nowhere to put
a cylinder?
Many people would like an unvented cylinder such as a Megaflo but do not know where it would go, because space is the issue. We work it out with you. It can go in an outhouse or a garage, or in a small timber structure next to or behind the house, as long as it is insulated and protected, and if that is not an option we can fit it in the loft, or where needed a horizontal cylinder in the eaves. It is not always straightforward, but we normally find a place that suits you.
In Southall the family were having a loft conversion and had no room for a cylinder anywhere else, so we fitted it in the eaves. In UB10 there was enough space down the side of the house for a small insulated timber structure, which now houses the cylinder, so they did not lose any space inside. In Kingston we have fitted them in the loft and in the lobby behind the stairs, and in Harrow, Wembley and Iver in purpose-built boiler rooms.
We fit Megaflo cylinders across all of London and the surrounding areas, from Chelsea to Hornchurch, St Albans, Maidenhead and Camberley.
Converting from
a loft tank
Swapping an old copper cylinder and loft tank for a Megaflo is a bigger job than replacing one Megaflo with another. The cold water tank and any pump come out, the pipework is changed to run at mains pressure, and the discharge pipe needs a proper route outside, which is the first thing we check on the survey.
Recent cylinder
installations
Gerrards Cross, SL9
Vaillant ecoTEC plus system boiler with a Megaflo unvented cylinder and wet underfloor heating, October 2026.
Hayes, Ruislip and Slough
Megaflo unvented cylinder installations across a landlord's rental properties, with annual servicing since (Google review).
Harrow
Baxi system boiler with a Megaflo unvented cylinder fitted in the loft, plus a water softener and air conditioning.
What to expect from
your installation
Assessment & Recommendation
We assess your property, existing system and hot water requirements and recommend the right cylinder type and size.
Quote & Scheduling
A written quote naming the cylinder and setting out exactly what will be done, at one fixed price. Scheduled at a time convenient for you.
Installation
Engineers install the cylinder and make all necessary connections to your heating system, cold mains and hot water outlets.
Testing & Safety Checks
Full test of all safety devices, pressure settings and thermostatic controls before sign-off.
Building Regulations & Documentation
All unvented cylinder installations require a Building Regulations notification. We handle this and provide all documentation.
Get in Touch
Free, no-obligation quote
Common questions about
Megaflo & cylinders
What is a Megaflo / unvented cylinder, and do I need one?
Will an unvented cylinder improve my water pressure?
How much does a Megaflo installation cost?
What size cylinder do I need?
Do unvented cylinders need servicing?
Can you install a cylinder in a large home with several bathrooms?
"The guys from DGN Gas were great. We needed them to replace a Megaflo. They were very courteous and respectful as well as being clean and tidy. They completed the job as requested and made sure everything was working well afterwards. Highly recommend."
"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."
Interested in a cylinder installation?
Call us for clear advice and a no-obligation quote. London-wide coverage for all installation work.
Get a Quote 07813 474638