Open vent system boilers are the boiler which requires two water tanks and one hot water storage cylinder. Generally these two water tanks are located in the loft area of the property. And the hot water cylinder is located in the store room of the property or flat. The water from one of the tanks is feed to the storage cylinder which is heated by the boiler, which can be used for hot water in the taps and bathroom and for any other purpose in the house.

When it comes to other water tank which is located in the loft area, it is called ‘feed and expansion tank’. This tank is used to maintain the correct level of water for the heating system. This tank helps for water expansion when the heat is turned on in the house. The main advantage of using open vent system boiler is that they can draw equal water at the same time when showers, taps and water heaters are switched on. The hot ware level in all the taps and showers will be same and it will not annoy you while taking shower. The big disadvantage is that it takes lot of time to reheat the water in the storage water cylinder. This means when the hot is finished you need to wait for long time use more hot water.

If you want to avoid additional water tank in your loft area and want to save some money and space, then the best choice it to switch to open vent sealed system boiler. Open Vent Sealed system boiler uses same technology and works similarly to open vent system boiler. But they don’t require second water tank with is located in the loft area.

Advantages and disadvantages of Open Vent System Boilers

Open Vented system boilers are more useful for houses or properties with 2 or more bathrooms. Because this boilers use hot water storage cylinder which helps in equal hot water supply for all the bathrooms at the same time. Another major advantage is that they are less expensive and easy to replace from one system to another.

Disadvantages are when the hot water runs our in the cylinder, it takes lot of time to reheat the cold water. This means you need to wait for more hot water. Another important disadvantage is that they are less energy efficient combi boilers.