Vented Cylinders (also known as Cistern Fed Cylinders) are suitable for use with Heat Only Boilers, which have a separate cold water storage cistern.
Up until the late 1980s, Vented Cylinders were the only type of cylinder used in homes, and they remain a popular choice as they’re easy to install and are less complicated than unvented cylinders. However, a pump may need to be installed to provide greater water pressure.
How do Vented Cylinders work?
Water from the mains supply is fed directly into the cold water storage cistern, at the top of the house. It will be stored here until it is needed. This is sometimes known as a Header Tank.
The Vented Cylinder has a pipe – or vent – at the top that connects it to the cold water storage.
When a hot water outlet is turned on, a heat exchanger will heat the water up and send the water from the storage tank into the Cylinder. The water passes using gravity, so sometimes a pump may be used to help strengthen the water flow.
The hot water will then move down pipework’s to wherever it is needed.
What are Vented Cylinders made from?
Vented Cylinders need to keep water hot, therefore it is necessary for them to be manufactured using metal that conducts heat. For this reason Copper is the most commonly used metal for water cylinders.
Cylinders are rated in grades, with the higher grading meaning the better the lifespan is likely to be, as it will have a higher resistance to corrosion. However, Vented Copper Cylinders, used in the home, are most likely to be Grade 3.
Pros of Vented Cylinders:
Vented Cylinders are less complicated than unvented ones, which makes them easier to install.
They are fairly cheap to purchase.
Vented Cylinders are easy to maintain.
Cons of Vented Cylinders:
Vented Cylinders connect to a cold water storage tank, which can take up a great deal of space
You should always consult a qualified Heating Engineer before making any final decisions about purchasing a hot water cylinder.