Vaillant Unistor Indirect 300

Overview

The Vaillant Unistor Indirect 300 is designed to support dependable stored hot water performance in domestic heating systems. It can form part of a wider installation where the right boiler parts and compatible components are needed for long-term reliability. For heating engineers and homeowners comparing boiler accessories, this product helps complete a practical hot water setup.

The Vaillant uniSTOR 300L Unvented Indirect Cylinder is a high-quality hot water storage solution, designed for domestic properties with new or existing sealed systems or open vent boilers. Ideal for larger homes with multiple bathrooms, this cylinder provides reliable hot water while improving system efficiency. Its slimline design allows flexible installation even in spaces where traditional cylinders may not fit.

Performance and Efficiency

• High-capacity 300 litres - perfect for larger households with multiple bathrooms
• Duplex stainless steel construction - long-lasting, robust, and corrosion-resistant
• Highly insulated - minimises heat loss, reduces running costs, and is environmentally friendly
• Unvented design - operates efficiently under higher pressures, providing strong water flow at taps and showers
• Retrofit-friendly - can replace older cylinders without the need to upgrade the entire system

Installation and Convenience

• Adjustable feet - suitable for installation on uneven floors
• Slimline and standard cylinder options - fits in more compact spaces
• Easy-to-clean outer casing - maintains a neat and hygienic appearance
• Compatible with sealed or open vent systems - ideal for conversions from loft tanks to space-saving sealed systems

Durability and Warranty

The uniSTOR 300 is built from high-grade stainless steel and comes with a 2-year parts and labour guarantee, as well as an industry-leading 25-year guarantee on the cylinder shell, providing peace of mind for homeowners and installers alike.

Why Choose Vaillant uniSTOR 300?

The uniSTOR 300L cylinder is perfect for homes seeking high-capacity, reliable hot water storage without compromising on space. By upgrading from an older copper cylinder, this unit significantly reduces heat loss, increases system efficiency, and delivers improved water pressure. Its durable build, advanced insulation, and compact design make it a long-term, cost-effective solution for larger properties.

FAQs

Q: What is the capacity of the Vaillant uniSTOR 300?

The cylinder has a 300-litre capacity, making it ideal for larger homes or properties with multiple bathrooms.

Q: Can the uniSTOR 300 be fitted to older heating systems?

Yes, it can be retrofitted onto existing systems, allowing an upgrade without replacing the entire heating setup.

Q: How energy-efficient is the Vaillant uniSTOR 300?

Thanks to its high-grade insulation, the cylinder minimises heat loss, helping to lower energy bills and improve overall system efficiency.

Check out our full range of plumbing supplies.

Browse more heating accessories available online.

At JJ Building Materials, we're committed to supplying quality building products at competitive prices, backed by the service and expertise you'd expect from an established independent merchant. Whether you're a trade professional managing large-scale projects or a homeowner taking on a DIY renovation, we're here to help you find the right products for the job.

As part of the JJ Roofing Supplies Group, we build on decades of experience supplying construction materials across the UK. We've expanded beyond roofing to offer a growing range of building materials, including timber, insulation, landscaping products, plumbing supplies, flooring, doors, bricks, fencing, garden buildings and much more – all available to order online with nationwide delivery.

We work with many of the industry's leading manufacturers to bring you trusted products that meet the highest standards of quality and performance. Our team is passionate about providing excellent customer service, competitive pricing and a straightforward shopping experience from start to finish.

When you shop with JJ Building Materials, you can expect:

• Competitive prices on leading brands and quality products.
• Nationwide delivery across the UK
  
• A constantly expanding range of building and landscaping materials.
  
• Friendly, knowledgeable customer support.
  
• A trusted business backed by the JJ Roofing Supplies Group.
  

Every order is personally reviewed by our experienced team to ensure everything is correct before dispatch. We offer delivery from as little as the next working day on selected products, so please refer to the dark blue Estimated Delivery box above for the expected delivery timeframe for this item.

We work with trusted manufacturers and specialist delivery partners to ensure your order arrives safely and on time. You'll receive tracking details once your order has been dispatched, and if we need to confirm any delivery details, one of our team will contact you directly to keep everything running smoothly.

Roof Tiles & Fittings:

We recommend ordering an additional 10% of roof tiles to allow for any breakages that may occur during delivery or handling. Roof tiles are naturally fragile, and having a few extra on site helps prevent delays and ensures your roofing project can be completed without interruption.