Kartell K-Rad Aspen Vertical Radiator 1800 x 540mm Single White - 4,309 BTU

In stock

SKU

ASP18-55VSW

£149.47

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Call an heating expert on 01282 429061

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Key Features

More Information
Manufacturer	Kartell UK Ltd
Manufacturer Warranty	5 Years (T&C’s Apply)
Weight	21.12kg
Orientation	Vertical Orientation
Panel Type	Single Panel Radiator
Colour	White
Height	1800 mm
Width	540 mm
Heat Output BTU	4309
Radiator Pipe Centres (mm) (Plus Valves)	540
Radiator Wall To Pipe Centres (mm)	40
Radiator Colour	White
Model	Aspen White Vertical Single
Brand	Kartell K-Rad
Fuel Type	Central Heating
Width (mm)	540
Depth (mm)	55
Height (mm)	1800
Manufacturer Part No	ASP18-55VSW

Product Details

Nearest vertical radiator to 1800x500mm 1800x510mm 1800x520mm 1800x530mm 1800x550mm 1800x560mm 1800x570mm 1800x580mm 1800x590mm 1800x600mm. Closest K-Rad Aspen to 1800 x 540mm. Kartell Aspen 1800mm tall 540mm wide white vertical radiator. ASP18-55VSW UK.

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Kartell K-Rad Aspen — Single White Vertical Radiator

Kartell K-Rad Aspen Vertical Radiator 1800 x 540mm Single White — 4,309 BTU

One of the UK's most popular oval tube designer vertical radiators in the widest standard size. Gloss white finish, mild steel construction, 55mm wall projection. 5 year Kartell manufacturer guarantee. All fixings included. Note — some competitors incorrectly list this radiator as 6,299 BTU. The correct certified output is 4,309 BTU as confirmed by Kartell UK.

4,309 BTU at Delta T60 1,263W 5 Year Guarantee Gloss White Oval Tube 1800 x 540mm SKU: ASP18-55VSW EAN: 5055681407483

4,309

BTU Delta T60

1,263W

Watts

1800

Height mm

540

Width mm

Depth mm

5yr

Guarantee

The Kartell K-Rad Aspen Vertical Radiator 1800 x 540mm Single White is the widest single panel size in the Aspen vertical range — and one of the highest-output oval tube designer radiators available at this price point. Delivering 4,309 BTU (1,263W) at Delta T60 from just 55mm wall projection, it is the ideal choice for larger hallways, open plan areas, living rooms, master bedrooms, and kitchens where both style and serious heat output are required. Backed by a 5 year manufacturer guarantee from Kartell UK with all fixings included. Please note — several competitors incorrectly list this radiator at 6,299 BTU. The certified output confirmed by Kartell UK is 4,309 BTU.

Free Delivery Over £500

5 Year Guarantee

All Fixings Included

UK Stock

Oval Tube Design

Why choose the Kartell K-Rad Aspen 1800 x 540mm White?

Widest Single Panel Aspen — Maximum Output in a Slim Profile

At 540mm wide the 1800 x 540mm is the largest single panel in the Aspen vertical range, delivering 4,309 BTU from just 55mm depth. More heat, same slim wall projection as the narrower sizes.

Ideal for Larger Rooms and Open Plan Spaces

With 4,309 BTU this radiator comfortably heats larger bathrooms, master bedrooms, open hallways, kitchens, and medium living rooms — rooms where the 420mm size would be borderline.

Certified 4,309 BTU — Not the Incorrect 6,299 BTU Listed Elsewhere

The correct output as confirmed by Kartell UK is 4,309 BTU. Several competitors incorrectly list this as 6,299 BTU. Our listing uses the accurate, verified figure so you can buy with confidence.

5 Year Kartell UK Manufacturer Guarantee

Registered directly with Kartell UK, covering all manufacturing defects from date of purchase. One of the strongest guarantees available on a designer radiator at this price point.

Oval Tube Design — Premium Look and Better Heat Distribution

The distinctive oval tube construction distributes heat more evenly than flat panel radiators, looks significantly more premium, and still projects just 55mm from the wall.

Heat Pump Compatible — TRV Ready

Compatible with air source and ground source heat pumps as well as all standard gas, oil, and combi boiler systems. Works with all standard thermostatic radiator valves for room-by-room control.

Searching for a size close to 1800 x 540mm?

Radiators are manufactured in standard sizes. If you searched for 1800 x 500mm, 1800 x 510mm, 1800 x 520mm or 1800 x 530mm — or 1800 x 550mm, 1800 x 560mm, 1800 x 570mm, 1800 x 580mm, 1800 x 590mm or 1800 x 600mm — this 540mm wide radiator is the closest available standard size and will very likely be the perfect fit for your space. The 540mm pipe centres suit the vast majority of standard UK central heating pipework. Need something narrower? See our 1800 x 420mm version (3,368 BTU).

Useful information

5 Year Guarantee

Covered by Kartell UK against all manufacturing defects from date of purchase.

Free Delivery

Free on orders over £500. We aim for 3-5 working days and always try sooner.

Returns Policy

Unused items in original packaging accepted within 14 days. Email info@plumbxtra.co.uk.

Complete Your Install

Valves sold separately. We stock pipe covers, bleed keys, inhibitor. Call 01282 429061.

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Important Delivery Notice — Please Read

Inspect your order before signing for it. Any damage, shortages, or incorrect items must be reported within 48 hours of receipt. We cannot process claims outside this timeframe. Retain all original packaging until completely satisfied.

Full Technical Specification

Specification	Detail
Product Name	Kartell K-Rad Aspen Vertical Radiator 1800 x 540mm Single White
SKU	ASP18-55VSW
EAN / GTIN-13	5055681407483
Height	1800mm
Width	540mm
Depth	55mm
Orientation	Vertical
Colour / finish	Gloss White
Material	Mild Steel
Style	Oval tube — Modern
BTU output (Delta T60)	4,309 BTU (Note: some competitors incorrectly list as 6,299 BTU — confirmed 4,309 from Kartell UK)
Watt output (Delta T60)	1,263W
BTU output (Delta T50)	3,400 BTU (approx)
Heat pump compatible	Yes
Fuel type	Central heating (gas, oil, or electric)
Pipe centres	540mm
Wall to pipe centres	51mm
Valve connection	1/2 inch BSP
Empty weight	22kg
Max working pressure	7.8 bar
Fixings supplied	Yes — all fixings included
Manufacturer guarantee	5 years — Kartell UK
Valves	Not included — sold separately (see Valves tab)

Which room size does this suit?

At 4,309 BTU (1,263W) this radiator comfortably heats rooms of approximately 54-66 sq ft — ideal for a large master bathroom, double bedroom, open hallway, or medium kitchen. For smaller rooms, our 1800 x 420mm (3,368 BTU) may be sufficient. Use the BTU Calculator tab for a precise recommendation.

Available sizes — Kartell K-Rad Aspen Single White Vertical Radiator

Cannot find your exact size? The 1800 x 540mm is the closest standard size to 1800 x 500mm, 510mm, 520mm, 530mm, 550mm, 560mm, 570mm, 580mm or 600mm. Radiators are manufactured in standard widths only.

Size (H x W)	BTU (Delta T60)	Watts	Pipe Centres	SKU
1800 x 300mm	2,392	701W	300mm	ASP18-31VSW
1800 x 420mm	3,368	987W	420mm	ASP18-43VSW
1800 x 540mm THIS PRODUCT	4,309	1,263W	540mm	ASP18-55VSW

Also available in textured grey — view full vertical radiator range.

Need a technical data sheet or dimension drawing? Email info@plumbxtra.co.uk.

Is this radiator powerful enough for your room?

Kartell K-Rad Aspen 1800 x 540mm — 4,309 BTU at Delta T60

At 4,309 BTU, this radiator suits rooms of approximately 54-66 sq ft in a well-insulated modern property — a large master bathroom, double bedroom, open hallway, or medium kitchen. Enter your room details below for a personalised calculation.

Free BTU Calculator

Enter your room dimensions below — we will calculate your exact heat requirement and confirm whether this radiator is the right choice.

Room Length (m)

Room Width (m)

Ceiling Height (m)

Room Type

Insulation Level

Glazing

Your estimated room heat requirement:

Understanding Delta T60 and heat pump output

All radiator heat outputs are quoted at Delta T60 — the European standard for testing, which assumes a mean water temperature 60°C above room temperature. Most modern combi boilers operate at or near this standard.

Heat pump users: At Delta T50, multiply by 0.789 — giving approximately 3,400 BTU. At Delta T41, multiply by 0.638 — giving approximately 2,749 BTU. Always size up when installing on a heat pump system.

How to install a designer vertical radiator — video guide

Watch our step-by-step installation guide below. Professional installation by a Gas Safe registered engineer is strongly recommended for all connections to gas central heating systems.

Installation notes

Pipe centres	540mm
Wall to pipe centres	51mm
Wall projection	55mm
Valve connection	1/2 inch BSP — angled, straight, or corner valves
Max working pressure	7.8 bar
Compatible systems	Sealed and open vented — gas, oil, electric, heat pump
Fixings supplied	Yes — wall brackets, screws, plugs, air vent, blanking plug
Valves	Not included — see Valves tab

Heat pump compatible: At Delta T50 flow temperatures, output is approximately 3,400 BTU. Always size correctly for heat pump installations — use the BTU Calculator tab.

Need the installation manual? Contact our team at info@plumbxtra.co.uk or call 01282 429061 and we will send it straight over.

Which radiator valves do I need?

Valves are not included and must be purchased separately. This radiator uses standard 1/2 inch BSP connections. Select your pipework configuration below.

Angled Radiator Valves

When to use: Pipework rises vertically from the floor and connects to the side connections of the radiator. The valve turns 90 degrees to make the connection.

This is the most common configuration in UK homes. If you are unsure which type you need, angled valves are most likely correct.

Pipe size: Standard 15mm angled valves fit the 1/2 inch BSP connections on this radiator.

Most popular choice — angled valves suit the majority of UK central heating installations.

Angled valves at PlumbXtra

Design Twin Pack TRV — White Angled

White finish — Angled — TRV + Lockshield

Design Twin Pack TRV — Chrome Angled

Chrome finish — Angled — TRV + Lockshield

Not sure? Call 01282 429061 — our team will advise.

Straight Radiator Valves

When to use: Pipework rises from the floor and connects directly to the bottom tappings of the radiator in a straight vertical line.

Used where the pipe exits the floor directly beneath the radiator. Less common than angled but frequently used in newer properties.

Pipe size: Standard 15mm straight valves fit the 1/2 inch BSP connections on this radiator.

If replacing an existing radiator that already has straight valves fitted, straight valves are the correct choice.

Straight valves at PlumbXtra

Design Twin Pack TRV — White Straight

White finish — Straight — TRV + Lockshield

Design Twin Pack TRV — Chrome Straight

Chrome finish — Straight — TRV + Lockshield

Design Twin Pack TRV — Textured Grey Straight

Grey finish — Straight — TRV + Lockshield

Not sure? Call 01282 429061 — our team will advise.

Corner Radiator Valves

When to use: Pipework comes horizontally out of the wall and connects to the side connections of the radiator.

Common in apartments, first-floor rooms, and properties where pipework runs through wall chases rather than up through the floor.

Pipe size: Standard 15mm corner valves fit the 1/2 inch BSP connections on this radiator.

Not sure which type you need? Call 01282 429061 — our heating engineers will advise.

Corner valves at PlumbXtra

Design Twin Pack TRV — White Corner

White finish — Corner — TRV + Lockshield

View all corner valve options

Full radiator accessories range at PlumbXtra

Not sure? Call 01282 429061 — our heating engineers will advise.

View our full radiator accessories range or call 01282 429061 for expert valve advice.

Frequently asked questions — Kartell K-Rad Aspen 1800 x 540mm White

Yes — the correct certified output is 4,309 BTU (1,263W) at Delta T60, as confirmed directly by Kartell UK in their official product brochure and on kartelluk.com. Several competitors incorrectly list this radiator at 6,299 BTU. This is an error. PlumbXtra lists only the accurate verified figure so you can size your heating correctly.

With 4,309 BTU (1,263W) at Delta T60, this radiator suits rooms of approximately 54-66 square feet — ideal for a large master bathroom, double bedroom, open hallway, or medium kitchen. Use the BTU Calculator tab for a precise personalised calculation.

Pipe centres are 540mm, with a wall to pipe centres measurement of 51mm. Compatible with the vast majority of UK central heating configurations. Angled, straight, or extended valve sets can bridge different pipe positions if needed.

Yes — 5 year manufacturer guarantee from Kartell UK, covering all manufacturing defects from date of purchase. One of the strongest guarantees available on a designer radiator at this price point.

Valves are not included and must be purchased separately. The correct type depends on your pipework: Angled — pipe rises from floor to side connection (most common). Straight — pipe rises from floor to bottom connection. Corner — pipe exits from wall to side connection. This radiator has 1/2 inch BSP tappings — standard 15mm valves are correct. See the Valves tab for all compatible products.

Yes — compatible with all wet central heating systems including combi boilers, system boilers, and heat-only boilers on gas or oil. Also compatible with air source and ground source heat pumps. At Delta T50 (heat pump typical flow temperature), output is approximately 3,400 BTU. Use the BTU Calculator tab for heat pump sizing.

Yes — suitable for bathroom installation by a qualified installer in compliance with Part P building regulations and current IET wiring regulations.

Delta T60 is the European industry standard for measuring radiator output — it assumes a mean water temperature 60°C above the room air temperature. For Delta T50, multiply by 0.789 giving approximately 3,400 BTU. For Delta T41 (typical heat pump temperature), multiply by 0.638 giving approximately 2,749 BTU.

Just 55mm from the wall — despite being the widest single panel in the Aspen vertical range, the depth remains 55mm identical to the narrower sizes. Wall to pipe centres is 51mm.

A straightforward radiator swap by a Gas Safe registered plumber typically costs between £100-£200 including labour. If new pipework is required, costs will be higher. Always obtain at least two quotes from qualified installers before proceeding.

Both are single panel, 55mm deep, and 1800mm tall. The key difference is width and output — the 1800x420mm produces 3,368 BTU and suits rooms up to approximately 52 sq ft. The 1800x540mm produces 4,309 BTU and suits larger rooms up to approximately 66 sq ft. The 540mm pipe centres on this model also require slightly wider pipework spacing. Use the BTU Calculator tab to determine which size is correct for your room.

Still have a question? Call our heating experts on 01282 429061 Mon-Fri or email us. We are happy to advise on radiator selection, valve types, BTU requirements, and installation.

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