MPN: TSMD090/ONYX

Onyx Direct Stainless Steel Unvented Cylinder

Onyx Direct Stainless Steel Unvented Cylinder

£302.03 Excl. VAT
£362.44 Incl. VAT
£302.03 Excl. VAT
£362.44 Incl. VAT

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Product Information

Onyx Direct Stainless Steel Unvented Cylinder

The Onyx Direct Stainless Steel Unvented Cylinder is a fully electric hot water solution designed for homes and apartments that aren’t connected to a traditional boiler system. Featuring two powerful 3kW immersion heaters — one for day-to-day timed use and another as a backup — it ensures reliable and efficient hot water whenever you need it. From 170L upwards, the primary immersion heater is upgraded with a Smart Eco thermostat, helping to maintain consistent temperatures while keeping energy use low. Built in the UK and made from high-grade Duplex stainless steel, the Onyx Direct Cylinder offers exceptional durability and corrosion resistance. It’s engineered to deliver strong, dependable performance for all-electric properties, making it a perfect choice for modern households, rental apartments and energy-efficient installations.

Complete G3-Approved Kit Included

Each cylinder comes with a full G3 unvented installation kit, including: Two Thermowatt 3kW immersion heaters (On 170L, 200L, 250L and 300L models, the second immersion is a Smart Immersion) Zilmet expansion vessel Caleffi tundish Caleffi 22mm inlet control group with pressure relief valve Factory-fitted Caleffi 7-bar / 90°C temperature & pressure relief valve Factory-fitted secondary return (supplied with 200L, 250L and 300L models) Available in a wide range of sizes — 90L, 125L, 150L, 170L, 200L, 250L and 300L, there's an option to suit everything from compact apartments to larger homes with higher hot water demand.

FAQs

Is this cylinder suitable for homes without a boiler?

Yes — this is a **direct** cylinder, meaning it heats water using immersion heaters only, making it ideal for 100% electric properties.

What is the Smart Eco immersion heater?

On models 170L and above, the main immersion heater includes a Smart Eco thermostat that learns usage patterns and heats water more efficiently.

Does the cylinder come with everything needed for installation?

Absolutely. The Onyx Direct cylinder includes a full G3 unvented kit with all essential safety and control components.

Download Data Sheet

Onyx Direct Stainless Steel Unvented Cylinder

£302.03

Can I collect this product from a local branch?

Absolutely. Check availability at your nearest branch during checkout or contact us directly.

Do you offer bulk pricing or trade discounts?

Yes, we offer competitive rates for trade customers and bulk orders. Contact our team for a tailored quote.

What if the product arrives damaged?

Please notify us within 48 hours of delivery. We’ll arrange a prompt replacement or refund as needed.

How fast is the delivery time?

Most items are delivered within 2–5 working days, depending on stock and location. Some products may take longer times.

What is the Return Policy?

We accept most returns within 14 days of delivery, provided the items are unused, in their original packaging, and in resalable condition. Please contact our customer service team to arrange a return or discuss any concerns.