Most homes will utilise hot water storage cylinders to supply hot water and due to the ease of installation, the majority of newly built properties will be fitted with unvented hot water systems.
These type of hot water systems work directly from the mains water and enables hot water to be supplied and because the pressure comes directly from the mains water the flow rate is much better compared to a vented water system. Unvented hot water systems have safety devices inbuilt to help it cope with the high pressure and expansion of water.
You may find you have a small tank sitting in the loft for venting and feeding your central heating, however, unvented cylinders provide hot water constantly at mains pressure, so there is no requirement for a cold water storage tank and the extra pipework to link it up. And because you’re relying on the pressure from the mains rather than just gravity, you can situate the hot water cylinder in almost any location.
An unvented hot water storage cylinder can be heated directly by an electric immersion heater, or indirectly by most heating systems – although appliances that burn solid fuel are the exception.
Unvented hot water systems do have certain advantages, not least because they are an efficient way of storing and distributing hot water throughout your home at mains pressure. Other advantages include:
- Fast filling baths
- Hot water at mains pressure
- No restrictions on wherein a property the system is installed
- No need for cold water storage
- Utilises existing pipework
- Drinking water at all taps
The main drawback with this system is that they are not compatible with all types of taps and showers. Besides the homeowner needs to be discerning when selecting the capacity of a cylinder, as buying something which is excessively large would mean vast quantities of heated water could go to waste and could generate a rise in energy bills.