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Hot Water Cylinder Installation: Our Guide

Purchasing a hot water cylinder isn’t exactly one of the most exciting buys, but it's necessary to ensure your household has hot water and working radiators, especially if there are young children or elderly and vulnerable people in your home or workplace.

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What is a hot water cylinder?

A hot water cylinder is a tank used for storing hot water. In the UK, there are two main types available: unvented cylinders and vented cylinders.

Our expert and qualified team are able to install and service both types of water cylinders.

Unvented Cylinder Installation

Unvented cylinders need to be installed by a qualified plumbing and heating engineer, who has completed their G3 unvented cylinder qualification.

Vented Cylinder Installation

Again, vented cylinders need to be installed by a qualified plumbing and heating engineer.

You don’t want to experiment installing it yourself, as the system operates under extreme pressure and a large volume of hot water. If the installation was to go wrong, it would have disastrous consequences for your household.

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What is the difference between a vented and unvented cylinder?

Unvented water cylinders receive water directly from the mains whereas vented water cylinders receive water from external water tanks stored in loft space.

As unvented water cylinders receive water directly from the mains, it benefits from greater levels of pressure, distributing water easily throughout your home.

They do not require a separate cold water tank, making them more compact than other systems which require loft space.

Vented water cylinders receive water from external cold water tanks which are typically stored in the loft. They are found in the loft as they rely on gravity to build pressure, rather than having the pressure generated from the mains.

It is called a vented hot water cylinder because a vent pipe is used to connect the hot water tank to the header tank.

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How do hot water cylinders work?

Hot water cylinders work by heating and storing the water in the tank for when you need it. There are two types of cylinders which can be found in the UK: direct and indirect cylinders.

 

What is a direct hot water cylinder?

A direct water cylinder uses heat sources which are located physically in the cylinder to heat the water. Typically, they use an electric heat immersion heater.

Direct cylinders tend to be located in premises where there is no access to gas, such as in high level flats or apartments.

Sometimes, direct water cylinders will have two immersion features which will allow you to take advantage of off-peak energy tariffs. This will minimise overall running costs.

 

What is an indirect hot water cylinder?

Indirect hot water cylinders typically use an external energy source, such as solar thermal systems or traditional central heating. This is fed into the cylinder by a coil or heat exchanger which then indirectly heats the hot water.

Most hot water cylinders also come with an electric immersion heater to act as a backup if the primary energy source fails.

 

Installing a hot water cylinder

At Lacey Plumbing and Heating, we can install your hot water cylinder for you.

Our expert team of professionals will be able to advise you on the best options suitable for your home, as well as your family needs.

 

What type of hot water cylinder do I need?

When choosing between hot water cylinders, there are a few key factors which you need to consider. 

If you have an old home, you are more likely to have a vented water cylinder. If you wish to have an unvented cylinder, it’s important to know that it could create a higher water pressure in your hot water pipes than your previous cylinder. 

If your mains pressure is quite low, then you may need to consider if an unvented cylinder is the best option for you as it will provide water from the mains at the same low pressure. If you do have a vented cylinder and low mains pressure, you can install an additional pump to push the flow of water. 

Depending on the size of your house, you may also want to consider your water cylinder. If you don’t particularly have a lot of space, then you should opt for an unvented cylinder. Vented cylinders require a lot of space, in a high position, in order to provide the gravity the system needs; something in which your home may be lacking.

Installing a hot water cylinder

When choosing between hot water cylinders, there are a few key factors which you need to consider.

If you have an old home, you are more likely to have a vented water cylinder. If you wish to have an unvented cylinder, it’s important to know that it could create a higher water pressure in your hot water pipes than your previous cylinder.

If your mains pressure is quite low, then you may need to consider if an unvented cylinder is the best option for you as it will provide water from the mains at the same low pressure. If you do have a vented cylinder and low mains pressure, you can install an additional pump to push the flow of water.

Depending on the size of your house, you may also want to consider your water cylinder. If you don’t particularly have a lot of space, then you should opt for an unvented cylinder. Vented cylinders require a lot of space, in a high position, in order to provide the gravity the system needs; something in which your home may be lacking.

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Replacing a hot water cylinder

Ideally, you should be using professional and qualified plumbers to replace your water cylinders to ensure everything is correctly fitted and fully functioning.

Before deciding on which cylinder you want, you will need to consider the factors previously discussed, such as:

  • The size of the cylinder;
  • The size of your home; and
  • The amount of people in your household who will be using water at the same time.

To replace a cylinder, you can expect it to take around three to four hours which will add additional costs onto payment for the cylinder and the installation itself.

Hot water cylinder servicing and maintenance

Lacey Plumbing and Heating can provide both hot water cylinder servicing and maintenance. Our professionally trained and experienced team will provide the best service possible, ensuring all your water cylinder issues are resolved as soon as possible.

If you have any more plumbing or heating related issues, check out our boiler servicing or boiler installation.

FAQs about Hot Water Cylinders