You’re browsing commercial products — Horizontal Unvented Cylinders is in our domestic range.
World Heat Cylinders · 0161 343 8610 · sales@whcylinders.co.uk
Domestic · Unvented cylinder
Horizontal Unvented Cylinders: Mains Pressure Hot Water for Restricted Spaces
Horizontal stainless steel unvented cylinders for lofts, eaves and anywhere height is limited — including Climacyl heat pump models.
- Lies horizontally where height is limited
- 120–500 L standard sizes
- SuperFlow and Climacyl heat pump models
- Duplex stainless steel vessel
- ErP class C
- 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
Lead time (ready for dispatch)
Checking today’s lead times…
Need it sooner? Call us — we can often expedite.
What’s included Specifications Datasheets & downloads
Made in Manchester- ISO 9001
- WRAS
- G3
What’s included
Supplied with every cylinder
SuperFlow models
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
Climacyl and EcoSlim heat pump models
Every Climacyl and EcoSlim heat pump cylinder comes with a full unvented kit. Heat pump models don’t need the boiler’s dual thermostat or zone valve.
- 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
Exact kit contents can vary with the cylinder size; we confirm them on your quotation.
About our unvented kits and spare partsTechnical data
Specifications
Climacyl Horizontal heat pump cylinders — 550 mm diameter (standard)
| Capacity (litres) | 120 | 150 | 180 | 210 | 250 | 300 |
|---|---|---|---|---|---|---|
| Length (mm) | 954 | 1154 | 1280 | 1468 | 1718 | 2031 |
| Diameter (mm) | 550 | 550 | 550 | 550 | 550 | 550 |
| ErP class | C | C | C | C | C | C |
Climacyl Horizontal heat pump cylinders — 600 mm diameter
| Capacity (litres) | 300 | 350 |
|---|---|---|
| Length (mm) | 1765 | 1960 |
| Diameter (mm) | 600 | 600 |
| Coil surface area (m²) | 3 | 3 |
| Standing heat loss (W) | 96 | 108 |
| ErP class | C | C |
Climacyl Horizontal heat pump cylinders — 700 mm diameter (standard)
| Capacity (litres) | 400 | 500 |
|---|---|---|
| Length (mm) | 1660 | 1960 |
| Diameter (mm) | 700 | 700 |
| Coil surface area (m²) | 3 | 3 |
| Standing heat loss (W) | 108 | 118 |
| ErP class | C | C |
SuperFlow Indirect Horizontal — 550 mm diameter (standard)
| Capacity (litres) | 120 | 150 | 180 | 210 | 250 | 300 |
|---|---|---|---|---|---|---|
| Length (mm) | 954 | 1154 | 1280 | 1468 | 1718 | 2031 |
| Diameter (mm) | 550 | 550 | 550 | 550 | 550 | 550 |
| ErP class | C | 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
Climacyl Horizontal heat pump cylinder product information sheetPDF · 686 KB (opens in a new tab)
Climacyl Horizontal Twin Coil heat pump cylinder product information sheetPDF · 703 KB (opens in a new tab)
SuperFlow Direct Horizontal cylinder product information sheetPDF · 686 KB (opens in a new tab)
SuperFlow Indirect Horizontal cylinder product information sheetPDF · 686 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 Horizontal Unvented Cylinders
World Heat Cylinders provides a comprehensive range of Horizontal Unvented Cylinders, expertly designed for installations where vertical height is limited. These space-saving solutions are perfect for locations such as lofts, attics, under eaves, or crawl spaces, delivering high-performance mains pressure hot water without compromising on capacity or efficiency.
Our Horizontal SuperFlow Unvented cylinder range, manufactured from high-quality stainless steel, is specifically engineered to provide maximum efficiency for horizontal unvented cylinder applications, with standard sizes from 120 to 500 litres and bespoke cylinders built to order.
Advantages of Horizontal Unvented Cylinders
Choosing a World Heat Cylinders Horizontal Unvented Cylinder offers several distinct benefits, especially for challenging installations:
- Space Efficiency: Primarily, their horizontal orientation allows installation in areas with restricted headroom where a standard vertical cylinder would not fit. This makes them ideal for maximising unused spaces.
- Mains Pressure Hot Water: Enjoy powerful showers and fast-filling baths, as these cylinders deliver hot water at mains pressure to all outlets.
- High Flow Rates: Designed to provide excellent flow rates, ensuring consistent hot water delivery even when multiple taps are in use.
- Durable Stainless Steel Construction: We manufacture our horizontal unvented cylinders from high-quality Duplex stainless steel, offering superior corrosion resistance and ensuring a long, reliable service life.
- High-Performance Insulation: Featuring foam-injected zero ozone depletion potential (ODP) insulation, these cylinders minimise heat loss, thereby improving energy efficiency and reducing running costs.
- Versatile Capacity Range: Standard horizontal sizes run from 120 to 500 litres, and we build bespoke sizes to order.
Applications & Bespoke Horizontal Solutions
Our horizontal unvented cylinders are suitable for a wide array of applications, including:
- Domestic properties with loft conversions or limited cupboard space.
- Apartments and flats where plant room height is restricted.
- Light commercial installations needing a space-saving mains pressure solution.
- New-build projects designed with horizontal cylinder placements.
- Retrofit applications replacing older horizontal tanks.
Bespoke Options Available On Request: We understand that standard sizes don't always fit every project. Consequently, if you require specific dimensions, connection orientations, or additional tappings for your horizontal unvented cylinder, please discuss your requirements with our technical sales support team. Indeed, we can often tailor a solution to meet your exact needs.
Quality & Manufacturing Standards
At World Heat Cylinders, we build every horizontal unvented cylinder to the highest standards:
- A 25 year guarantee on stainless steel unvented cylinders up to 300 litres reflects 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.
- We use foam injected zero ozone depletion insulation for superior thermal performance.
- While the inner vessel is stainless steel, units can be supplied with a high-grade white coated galvanised steel finish for external durability and aesthetics.
- All our cylinders are British Manufactured under a BSI audited ISO9001 quality management system, ensuring consistent quality and reliability.
Discuss Your Horizontal Unvented Cylinder Project
For expert advice on selecting the correct Horizontal Unvented Cylinder, or to discuss a bespoke design for your space-restricted application, please contact our technical sales support team.
Therefore, call us today on 0161 343 8610, email sales@whcylinders.co.uk, or get in touch online.
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.