Unvented Hot Water Cylinders London
Installation, replacement and servicing of unvented hot water cylinders across London. G3 qualified engineers. Megaflo, Gledhill and Heatrae Sadia specialists.
0800 123 4567An unvented hot water cylinder stores mains-pressure hot water, delivering powerful flow to all outlets simultaneously - no cold spots in the shower, no waiting for the tank to refill. Unlike traditional vented cylinders, there is no need for a cold water tank in the loft. Installation must be carried out by a G3 qualified engineer to comply with Building Regulations.
Unvented Cylinder Cost London - 2026 Prices
| Service | Typical Cost |
|---|---|
| Unvented Cylinder Supply & Install | £1,200–£2,500 |
| Cylinder Replacement | £900–£1,800 |
| Annual Service | £120–£200 |
| Pressure Relief Valve | £80–£150 |
| Immersion Heater Replacement | £120–£200 |
| Expansion Vessel Replacement | £100–£180 |
* Prices are estimates for London. Fixed price confirmed before work begins. Building Regulations notification included.
Unvented Cylinder Installation & Servicing Across London
Unvented hot water cylinders deliver mains-pressure hot water throughout the property without the need for a cold water storage tank in the loft. This means stronger shower pressure, no cold water tank maintenance and a more efficient hot water system overall.
Our G3 qualified engineers install, service and repair all major brands including Megaflo, Gledhill, Heatrae Sadia and Kingspan. All installations include Building Regulations Part G3 notification and a full commissioning report.
Unvented Cylinder Services
- Unvented Cylinder Installation
- G3 Building Regulation Compliance
- Megaflo & Gledhill Specialists
- Annual Servicing & Inspection
- Pressure Relief Valve Checks
- Immersion Heater Repair
- Expansion Vessel Replacement
- Legionella Risk Assessment
Frequently Asked Questions
What is an unvented hot water cylinder?
An unvented cylinder connects directly to the mains cold water supply and heats water to mains pressure. This delivers strong, consistent hot water flow to all outlets without the need for a header tank in the loft. Popular brands include Megaflo, Gledhill and Heatrae Sadia.
Do I need a special engineer?
Yes - unvented cylinder installation and servicing must be carried out by a G3 qualified engineer under Building Regulations Part G3. All our engineers hold current G3 qualifications and provide the required Building Regulations notification.
How often should an unvented cylinder be serviced?
Manufacturers recommend annual servicing. During a service we check the pressure relief valve, expansion vessel pre-charge, thermostat settings and safety devices. Neglecting servicing can void the manufacturer warranty and create safety risks.
Call Us Now
G3 qualified engineers. Building Regulations notification included with all installations.
0800 123 4567