The Benefits of Unvented Hot Water Cylinders
Fed up with weak shower pressure and waiting for hot water? An unvented hot water cylinder could be the solution. These systems are becoming increasingly popular in UK homes, and for good reason.
What Is an Unvented Cylinder?
Unlike traditional vented cylinders that rely on a cold water tank in the loft and gravity to create pressure, unvented cylinders are connected directly to the mains water supply. This means they can deliver hot water at mains pressure throughout your home, without needing a header tank.
Mains Pressure
Powerful water flow at every outlet
Quick Recovery
Fast reheat times for hot water
Consistent Temp
Stable temperature throughout
Key Benefits
Powerful Shower Pressure
The most noticeable benefit is the dramatic improvement in water pressure. Enjoy powerful showers without needing a pump, and run multiple taps or showers simultaneously without significant pressure drop.
No Cold Water Tank Required
Without the need for a loft tank, you gain valuable storage space and eliminate the risk of frozen or contaminated water tanks. This also means fewer pipes in unheated areas that could freeze in winter.
Flexible Installation
Unvented cylinders can be installed almost anywhere in your home, not just in the loft or airing cupboard. This gives you more options for placement and can make installation easier.
Quieter Operation
Unlike systems that require pumps to boost pressure, unvented cylinders operate quietly using mains pressure alone. No humming pumps or water hammer noises.
Cleaner Water
Since the water comes directly from the mains rather than sitting in a tank, it's fresher and less likely to be contaminated by debris or bacteria that can accumulate in storage tanks.
Compatible with Solar and Heat Pumps
Many unvented cylinders can be paired with solar thermal panels or heat pumps, helping you reduce energy costs and your carbon footprint.
Things to Consider
Mains Pressure Requirements
Unvented cylinders need adequate mains water pressure and flow rate to work effectively. If your mains pressure is low (common in some older properties or rural areas), an unvented system may not be suitable. A professional assessment can determine this.
G3 Qualified Installation
Due to the high pressures involved, unvented cylinders must be installed by an engineer with a G3 qualification. This is a legal requirement and ensures the safety features are correctly fitted and tested.
Annual Service Required
Unvented cylinders contain safety devices that must be checked and serviced annually. This includes the pressure relief valve, expansion vessel, and temperature controls. Regular servicing is essential for safe operation.
Higher Upfront Cost
Unvented cylinders typically cost more to purchase and install than vented systems. However, many homeowners find the improved performance and convenience worth the investment.
Types of Unvented Cylinders
- Direct: Heated by immersion heaters. Good for properties without a boiler.
- Indirect: Heated by a boiler via a coil inside the cylinder. Can also have an immersion heater backup.
- Solar compatible: Features additional coils for connection to solar thermal panels.
- Heat pump ready: Designed to work efficiently with air or ground source heat pumps.
Popular Brands
At Elite Blue Gas, we install and service unvented cylinders from leading manufacturers including Megaflo, Heatrae Sadia, OSO, Gledhill, and Telford. We'll help you choose the right size and model for your household's hot water demands.