Unvented Hot Water Systems

Specialist Supply & Installation of Unvented Hot Water Systems

Leeva Plumbing & Heating are specialists in the supply and installation of unvented hot water systems.

There are 2 main types of water heaters used in residential homes; vented and unvented.

Unvented hot water systems require no cold water tank and offer “on demand” hot water. Instead the hot water cylinder stores water from the mains supply, which is then heated either from the boiler or using electrical heating elements.  When there is a need to for hot water, the pressure from the incoming cold water displaces the hot water in the cylinder and sends it to the required outlet (tap, shower, bath, etc).   This means that there should be increased pressure without the need for pumps.

Unvented hot water systems require an expansion vessel either next to them or incorporated within the boiler or cylinder. This allows for the expansion of water in the system as it heats up within the sealed unit.  The correct installation of an unvented hot water system and associated pressure equipment makes them an extremely safe piece of equipment to use.

The Benefits Of Unvented Hot Water Systems

There are several benefits to installing an unvented hot water system. Here are just a few: 

1. Improved water pressure. Because the system is being directly supplied with mains water and not relying on a tank in your loft or gravity to feed the system, water pressure tends to be improved with an unvented system.
2. Free Up space. Unvented cylinders require much less room as they don’t need a feeder tank and can also be slimline, meaning that you have much more space within your home.
3. No Location Restrictions. Unlike vented water systems, unvented systems don’t rely on gravity, so they can be installed almost anywhere in your home.
4. Reduced Noise. Unvented hot water systems tend to be quieter than vented systems, mainly due to the fact that the cold water is not filling up constantly in the storage cistern.
5. No Contamination. Because unvented systems are completely sealed and there’s no large tank of water in your loft, the water isn’t at risk of contamination.
6. Less Chance of Freezing. Because you don’t have a water tank with an unvented system and your water is being taken directly from the mains, there’s no chance of your tank freezing.

Types Of Unvented Hot Water Systems

There are various types and sizes of unvented hot water systems, ranging from 90 to 400 litres capacity (for domestic supply).  You can also choose from:

• Standard unvented cylinders
• Pre-plumbed unvented cylinders
• Horizontal unvented cylinders
• Slimline unvented cylinders
• Solar unvented cylinders