What are Unvented Cylinders?

Boiler Repair

February 4, 2022

What are Unvented Cylinders?

With the continuing development and innovation in water heating throughout history, there are many different types of hot water systems available today for homeowners, making it difficult for us to know which heating system is ideal for your house. 

For instance, if you are currently using an unvented cylinder system for your hot water supply, it’s important to understand how they work and what the right maintenance procedures are. This blog post will provide all of this information in detail so that homeowners can make a more informed decision about which heating system is best suited to their home, specifically which type of hot water system they should be using.

We will also look at the different types of unvented cylinders available, including their pros and cons, as well as how they work to heat your home’s water supply. We will then discuss why it is important for homeowners to maintain these systems correctly to avoid any problems with their hot water supply.

What are Unvented Cylinders?

Unvented cylinders are a popular type of heating system because they take up less space in the home and can be easily installed into your existing plumbing set up by a qualified plumber. They also provide homeowners with an unlimited amount of hot water, making them ideal for large households or homes with multiple bathrooms where everyone is trying to have their shower before heading out for the day.

However, they are not as popular with homeowners who are concerned about being able to control the temperature of their hot water supply, considering that unvented cylinders do not give you direct access to your heating system like other types of systems available on the market today. This means that if you live in an area where the water temperature can drop to very low temperatures, such as Scotland, you may struggle with having a constant supply of hot water over the winter months.

How Does Unvented Cylinder Work?

Unvented cylinders work by using either natural gas or propane to heat your home’s cold water supply which is then delivered directly into your taps (provided you have a constant water pressure), and stored in an unvented cylinder. The cold water flows through the cylinder to be heated by either gas or propane, which is then transferred into your hot water supply system for immediate use when required.

As well as using natural gas or propane to heat your home’s hot water supply, you can also use electricity to heat your hot water supply. This is usually an option only if you are unable to access natural gas or propane in the area where you live.

If you opt for unvented cylinders that run off of electric heating systems, it is important for homeowners who want them installed into their home’s plumbing systems to understand that they will need a separate electricity supply installed into their home specifically for the heating system and hot water. They also come with an electrical storage tank which can be located either in your loft or outside of your property – it depends on whether you have space available.

What are the Different Types of Unvented Cylinders?

Unvented cylinders come in different types, which vary according to their size and capacity depending on your home’s hot water needs. These include 500-litre unvented cylinders, 340-litre unvented cylinders, 240-litre unvented cylinders and 120-litre unvented cylinders. The larger the cylinder, the more hot water your home will have available to it on demand at any one time.

This is important for homeowners who live in large homes with multiple bathrooms or families that require a lot of hot water each day to keep their supply running smoothly without having to wait too long for the next hot water to be available.

You can also choose between either a direct system, which is where your cylinder and heating source is located in your home’s loft space above your bathroom or kitchen; or an indirect unvented cylinders system, which requires you to install it into the wall of your property close to your boiler.

What is The Advantage of Unvented Cylinders?

If you choose to go with an unvented cylinder system for your home’s heating and hot water supply, there are several advantages that it could provide if installed correctly by a qualified plumber. These include: 

  • Easily installed into your existing plumbing set-up, with the minimum of fuss.
  • Provides homeowners with an unlimited amount of hot water, so there is never any need to run out when you want a nice relaxing bath or shower after returning home from work tired and stressed.
  • Unvented cylinders are ideal for large households or homes with multiple bathrooms where everyone is trying to have their shower before they leave for work or school in the morning.
  • Provides homeowners with a supply of hot water throughout the year without any need to worry about the temperature dropping during the winter months. This is because it uses either natural gas or propane to heat your home’s cold water supply which then flows into your taps once heated and stored in an unvented cylinder.

What is The Disadvantage of Unvented Cylinders?

Even though there are many disadvantages of having unvented cylinders at your home, this heating system also has its downside. Below, you will find some of the disadvantages of installing this type of heating system in your home. These disadvantages with owning an unvented cylinder system include: 

  • If you live in an area where your water temperature drops low during the winter months, then you may struggle to get enough hot water to run your bath or shower without running out of hot water before you’ve finished washing.
  • You will need to keep the cylinder filled with either natural gas or propane for it to work, which can be costly depending on how often you use your home’s heating system and hot water supply. This is particularly important if your heating system is oil-fired and not gas-fired.
  • You will also need to install a separate electrical supply into your home’s plumbing circuit if you want to run the hot water cylinder as well as any other appliances such as washing machines, dishwashers or boilers which all require an electricity supply for them to function correctly.

What are Some Tips for Maintaining Unvented Cylinders?

To keep your unvented cylinders working correctly, you will need to carry out routine checks and maintenance on them to ensure that they are heating your home’s water supply thoroughly so they can be used when needed most. This includes: 

  • Checking for leaks every week and repairing any minor damage as soon as possible so you can avoid the problem becoming worse over time.
  • If your cylinder is located in your home’s loft space above an unoccupied room, then it would be advisable to turn off the gas supply at its mains shut-off valve but only if it is safe to do so. If the cylinder is located near your boiler or hot water tank, then you should ensure that its mains gas supply at the meter has been turned off completely and any appliances connected to this are also switched off too.
  • If an unvented cylinders system includes a secondary heating source such as solar panels on top of your roof or a radiator, then you may need to turn this off or down during the winter months if it is located in an area of your home that does not get any sunlight.
  • As unvented cylinders require either natural gas or propane for them to work correctly and safely, you will also need to ensure that at least one cylinder is filled with gas at all times so it can heat your water supply when needed most. This is particularly important if you have an unvented cylinder system that has a boiler or hot water tank connected to its mains gas supply which feeds into the main heating circuit of your home.
  • If you are new to owning, installing and maintaining unvented cylinders at your home, then you will need to ensure that the cylinder’s gas supply is fitted by a qualified and registered engineer or plumber. We suggest you hire trusted and professional heating & plumbing services to carry out any maintenance and installation work for you. If you are located in Camden, Hampstead, Golder’s Green, Westminster, Highgate, Maida Vale or any other part of London, you can contact Rare Heating & Plumbing Services. RARE Heating & Plumbing Services offer a wide range of first-class services in London to all customers, from private residences through to large commercial and industrial worksites. From a simple noisy boiler to high-level plumbing installations — we are well-equipped to take on any type of London plumbing and heating project.

We hope this post will help you learn more about unvented cylinders and how to maintain them. If you need any assistance in installing or maintaining unvented cylinders at your home,  please contact Rare Heating & Plumbing today! We are available 24/7 to respond to emergency call-outs and ensure you stay warm and dry.  Talk to you soon!

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