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World Heat Cylinders · 0161 343 8610 · sales@whcylinders.co.uk
Domestic · Unvented cylinder
Stainless SuperFlow Unvented Cylinders
Our premium unvented cylinder: Duplex stainless steel, direct or indirect, in slimline and standard diameters. Larger and bespoke sizes built to order.
- Direct and indirect, 90–300 L standard sizes
- Duplex stainless steel vessel
- ErP class B–C
- 50 mm PU foam insulation
- Supplied with unvented kit
- 25 year guarantee on stainless steel unvented cylinders up to 300 litres, subject to annual servicing
- Stainless steel cylinders over 300 litres: 12 months on the vessel, against a material defect or manufacturing fault
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What’s included Specifications Datasheets & downloads
Made in Manchester- ISO 9001
- WRAS
- G3
What’s included
Supplied with every cylinder
Every SuperFlow cylinder comes with a full unvented kit, so you have everything you need for a G3-compliant installation.
- Expansion vesselTakes up the water’s expansion as it heats
- Inlet manifold blockPressure reducing valve, pressure relief valve, strainer and check valve in one block
- Temperature and pressure relief (T&P) valve
- TundishThe visible air gap on the discharge pipe
- Dual mechanical thermostatControl and high-limit thermostat for the boiler coil (indirect models)
- Two-port zone valveControls the boiler’s flow to the coil (indirect models); we confirm it on your quotation
Exact kit contents can vary with the cylinder size; we confirm them on your quotation.
About our unvented kits and spare partsTechnical data
Specifications
SuperFlow Indirect — 475 mm diameter (slimline)
| Capacity (litres) | 120 | 150 | 180 | 210 |
|---|---|---|---|---|
| Height (mm) | 1208 | 1474 | 1690 | 2003 |
| Diameter (mm) | 475 | 475 | 475 | 475 |
| ErP class | B | C | C | C |
SuperFlow Direct — 475 mm diameter (slimline)
| Capacity (litres) | 90 | 120 | 150 | 180 | 210 |
|---|---|---|---|---|---|
| Height (mm) | 990 | 1208 | 1474 | 1690 | 2003 |
| Diameter (mm) | 475 | 475 | 475 | 475 | 475 |
| ErP class | B | B | C | C | C |
SuperFlow Indirect — 550 mm diameter (standard)
| Capacity (litres) | 90 | 120 | 150 | 180 | 210 | 250 | 300 |
|---|---|---|---|---|---|---|---|
| Height (mm) | 792 | 954 | 1154 | 1280 | 1468 | 1718 | 2031 |
| Diameter (mm) | 550 | 550 | 550 | 550 | 550 | 550 | 550 |
| ErP class | B | B | B | C | C | C | C |
SuperFlow Direct — 550 mm diameter (standard)
| Capacity (litres) | 90 | 120 | 150 | 180 | 210 | 250 | 300 |
|---|---|---|---|---|---|---|---|
| Height (mm) | 792 | 954 | 1154 | 1280 | 1468 | 1718 | 2031 |
| Diameter (mm) | 550 | 550 | 550 | 550 | 550 | 550 | 550 |
| ErP class | B | B | C | C | C | C | C |
Figures are from our current product data; each range’s product information sheet is linked under its table. Connection positions are confirmed on the drawing for each order. Other sizes and configurations are built to order.
Must be installed by a qualified unvented (G3) installer and registered with building control.
Documents
Datasheets & downloads
Datasheets
Stainless SuperFlow Direct cylinder product information sheetPDF · 691 KB (opens in a new tab)
Stainless SuperFlow Direct Slimline cylinder product information sheetPDF · 690 KB (opens in a new tab)
Stainless SuperFlow Indirect cylinder product information sheetPDF · 673 KB (opens in a new tab)
Stainless SuperFlow Indirect Slimline cylinder product information sheetPDF · 672 KB (opens in a new tab)
Installation & service manuals
ErP labels & data
Certificates
Brochures
Can’t find a document? Search the downloads library, browse all product datasheets and manuals, or email sales@whcylinders.co.uk.
In detail
About Stainless SuperFlow
The World Heat Cylinders' Stainless SuperFlow range represents our premium line of stainless steel unvented cylinders. Manufactured from high-quality, corrosion-resistant stainless steel, these cylinders are meticulously designed to deliver maximum efficiency and exceptional durability for a wide array of unvented hot water applications. Standard SuperFlow sizes run from 90 to 300 litres, in slimline (475 mm) and standard (550 mm) diameters, with larger and bespoke cylinders built to order.
Key features that define the SuperFlow range include high-density foam injected zero ozone depletion potential (ODP) insulation for minimal heat loss, and a robust, plastic-coated galvanised steel case. Every unit is manufactured in our UK facility under strict ISO 9001 quality management systems.
Core Benefits of the SuperFlow Range
Choosing a Stainless SuperFlow unvented cylinder from World Heat Cylinders offers numerous advantages:
- Exceptional Durability: Constructed from high-grade stainless steel for superior corrosion resistance and a long operational lifespan.
- High Efficiency: Thick, eco-friendly foam insulation minimises standing heat losses, contributing to lower energy bills.
- Mains Pressure Hot Water: Delivers excellent flow rates to multiple outlets simultaneously.
- Wide Range of Capacities: Standard sizes from 90 to 300 litres, with larger and bespoke cylinders built to order.
- Peace of Mind: Backed by a 25 year guarantee on stainless steel unvented cylinders up to 300 litres, reflecting our confidence in the materials and manufacturing expertise.
- Stainless steel cylinders over 300 litres: 12 months on the vessel, against a material defect or manufacturing fault.
- Quality Assured: Manufactured in the UK to ISO 9001 standards, ensuring consistent quality and reliability.
Bespoke SuperFlow Options & Customisation
While our standard SuperFlow range is extensive, we understand that some projects require tailored solutions. At World Heat Cylinders, we offer bespoke manufacturing options for the Stainless SuperFlow range. This allows for modifications to tapping sizes and positions, specific sensor pocket requirements, or integration with non-standard heat sources. Furthermore, we can discuss custom dimensions where feasible to fit challenging plant room spaces.
To discuss your specific customisation needs for a SuperFlow stainless steel unvented cylinder, please contact a member of our technical sales support team on 0161 343 8610 or email sales@whcylinders.co.uk.
Uncompromising Quality & Manufacturing Standards
The exceptional quality of our Stainless SuperFlow unvented cylinders is underpinned by our commitment to superior materials and meticulous manufacturing processes. Key quality aspects include:
- A 25 year guarantee on stainless steel unvented cylinders up to 300 litres, reflecting the quality of materials and our manufacturing expertise.
- Stainless steel cylinders over 300 litres: 12 months on the vessel, against a material defect or manufacturing fault.
- Durable plastic-coated galvanised steel case.
- Efficient foam injected insulation with zero ozone depletion potential (ODP).
- All units are manufactured to meet stringent ISO 9001 quality assurance standards.
Help choosing and specifying
Guides and tools
- Will it fit? Cylinder space checkerEvery cylinder that fits your cupboard or plant space
- Replace an existing cylinderThe World Heat equivalent of the cylinder there now
- Hot water storage sizing calculatorStorage volume and reheat time, homes and commercial
- Legionella and safe hot water storageHSE L8 and HSG274 temperatures for stored hot water
Explore the range
Related products
Need this tailored to your project or system?
Different connections, coil, size, controls or finish: our design team builds to your requirements.
We also build own-brand ranges for OEM partners.
Need a cylinder built to your specification?
From 10 litres to 10,000 litres, our Manchester team designs, manufactures and tests every vessel in-house. We confirm and respond to every bespoke enquiry within 48 hours, and standard range enquiries immediately. If you need a price on a standard product, don’t hesitate to call and speak to one of our team on 0161 343 8610.We confirm and respond to every bespoke enquiry within 48 hours, and standard range enquiries immediately. If you need a price on a standard product, don’t hesitate to call and speak to one of our team on 0161 343 8610.We confirm and respond to every bespoke enquiry within 48 hours, and standard range enquiries immediately. If you need a price on a standard product, don’t hesitate to call and speak to one of our team on 0161 343 8610.