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Vaillant uniSTOR Hot Water Cylinder

The uniSTOR cylinder, made of high-quality stainless steel, is a hot water storage device. It’s ideal for homes with an existing or new sealed system or open vent boiler. uniSTOR cylinders can be operated efficiently at higher pressures (e.g. in a sealed heating system).

Vaillant uniSTOR hot water storage cylinders are suitable for converting an open vented system with a cold water tank in a loft to a sealed system. This will save space and increase water pressure. 

As part of a heating system upgrade, you can convert an old copper cylinder into a new uniSTOR unvented hot water storage cylinder. This will reduce cylinder heat loss and improve your heating system’s efficiency.

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Vaillant uniSTOR unvented cylinder system and your home

The uniSTOR can be used in almost any property that has a sealed system or open vent boiler. Heating systems that use a cylinder are more suitable for larger properties with multiple bathrooms. They can provide hot water at a higher level than combination boilers.

Vaillant uniSTOR unvented Cylinders can be used to convert from an open vented system with a cold water tank in a loft to a sealed system. Converting to a sealed systems can help you save space, e.g. When there is not enough space for a tank, such as loft conversions or when you need to have more water pressure in your shower and taps.

You can improve the efficiency of your heating system by upgrading an old copper cylinder with insulation jacket to a uniSTOR unvented cylinder as part of a heating systems upgrade. This will reduce your cylinder heat loss significantly which can in turn help you to lower your fuel costs.

Read our review of the best system boilers to go with the latest unvented hot water cylinders right now.

UniSTOR hot water cylinder range

  • The range includes standard and slimline cylinders, as well as pre-plumbed cylinders.
  • You can rest assured knowing that the parts and labor are covered by a 2-year guarantee. The cylinder shell is covered by a 25-year guarantee.
  • You can retrofit your cylinder onto an older system, so you can upgrade without having to replace the whole system.
  • Insulation that is better means less heat loss and lower operating costs
  • The cylinder has adjustable feet that allow it to be placed on uneven ground.

Why choose the uniSTOR unvented cylinder?

Being one of the best hot water cylinders available, the Vaillant uniSTOR cylinder range was designed to be used in conjunction with Vaillant heat pumps and provide high-efficiency heating and hot water systems. UniSTOR heat pump cylinders provide a durable and long-lasting solution for your Vaillant heat pumps. They feature state-of-the-art insulation, as well as a 100% recyclable shell made of stainless steel. All Vaillant hot-water cylinders comply with the Hot Water Association’s standards.

  • The cylinders are available in a range of 150 to 300 litres. They’re therefore suitable for many properties with differing hot water requirements.
  • Vaillant heat pumps are specifically designed to be used with these products.
  • The unique integrated coil system provides maximum heat transfer, reduces running costs, and improves hot water performance.
  • The cylinders are made of 100% recyclable stainless steel and come with a tough-wearing outer shell. This comes with a 25 year guarantee
  • Available in sizes ranging from 150 to 300 litres
  • Available in pre-plumbed versions from 150 to 300 litres

Check out some of the other boiler manufacturers that make hot water cylinders like the Viessmann Vitocell unvented system. These are some of the most energy efficient in the UK right now.

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