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Kartell K-Rad Aspen Vertical Radiator 1800 x 420mm Single White - 3,368 BTU

In stock
SKU
ASP18-43VSW
£119.98

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Call an heating expert on 01282 429061

Key Features

More Information
Manufacturer Kartell UK Ltd
Manufacturer Warranty 5 Years (T&C’s Apply)
Orientation Vertical Orientation
Panel Type Single Panel Radiator
Colour White
Height 1800 mm
Width 420 mm
Heat Output BTU 3368
Radiator Pipe Centres (mm) (Plus Valves) 420
Radiator Wall To Pipe Centres (mm) 40
Radiator Colour White
Model Aspen White Vertical Single
Brand K-Rad Designer Range
Fuel Type Central Heating
Width (mm) 420
Depth (mm) 55
Height (mm) 1800
Manufacturer Part No ASP18-43VSW

Product Details

Nearest vertical radiator to 1800x400mm 1800x410mm 1800x415mm 1800x425mm 1800x430mm 1800x440mm 1800x450mm 1800x460mm 1800x470mm 1800x480mm. Closest K-Rad Aspen to 1800 x 420mm. Kartell Aspen 1800mm tall 420mm wide white vertical radiator. ASP18-43VSW UK.

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Kartell K-Rad Aspen — Single White Vertical Radiator

Kartell K-Rad Aspen Vertical Radiator 1800 x 420mm Single White — 3,368 BTU

One of the UK's best-selling oval tube designer vertical radiators. Gloss white finish, mild steel construction, 55mm wall projection. 5 year Kartell manufacturer guarantee. All fixings included.

3,368 BTU at Delta T60 987W 5 Year Guarantee Gloss White Oval Tube 1800 x 420mm SKU: ASP18-43VSW EAN: 5055681407445
3,368
BTU Delta T60
987W
Watts
1800
Height mm
420
Width mm
55
Depth mm
5yr
Guarantee
The Kartell K-Rad Aspen Vertical Radiator 1800 x 420mm Single White is one of the UK's best-selling oval tube designer vertical radiators. Built from mild steel with a high quality gloss white finish, it delivers 3,368 BTU (987W) at Delta T60 whilst projecting just 55mm from the wall. At 1800mm tall and 420mm wide it is the ideal choice for hallways, bathrooms, bedrooms, and kitchens where space is limited. Backed by a 5 year manufacturer guarantee from Kartell UK with all fixings included.
Free Delivery Over £500
5 Year Guarantee
All Fixings Included
UK Stock
Oval Tube Design
Why choose the Kartell K-Rad Aspen 1800 x 420mm White?
1

Oval Tube Design — Slimmer and More Stylish Than Flat Panel

The distinctive oval tube construction gives better heat circulation, a slimmer 55mm profile, and a far more premium aesthetic than standard flat panel radiators at similar price points.

2

Perfect for Tight Spaces — Only 420mm Wide

At 1800mm tall and just 420mm wide it fits neatly in narrow hallways, beside doors, between windows, and in bathrooms where a conventional horizontal radiator simply will not fit.

3

3,368 BTU — Independently Verified

Heat output tested at Delta T60. This is the actual certified output — not an estimated figure. Suitable for large bathrooms, single bedrooms, and hallways up to approximately 42-52 sq ft.

4

5 Year Kartell UK Manufacturer Guarantee

One of the strongest guarantees available at this price point. Registered directly with Kartell UK and covers all manufacturing defects from date of purchase.

5

Energy Efficient — Compatible with TRVs and Heat Pumps

The oval tube design heats quickly and retains heat efficiently. Compatible with thermostatic radiator valves (TRVs) for room-by-room control, and suitable for air source and ground source heat pump systems.

6

Ready to Install — All Fixings Included

Wall brackets, fixing screws, wall plugs, air vent and blanking plug all supplied. Add valves and it is ready to hang. Valves sold separately — see the Valves tab above.

Searching for a size close to 1800 x 420mm?

Radiators are manufactured in standard sizes. If you searched for 1800 x 400mm, 1800 x 405mm, 1800 x 410mm or 1800 x 415mm — or 1800 x 425mm, 1800 x 430mm, 1800 x 435mm, 1800 x 440mm, 1800 x 450mm, 1800 x 460mm, 1800 x 470mm or 1800 x 480mm — this 420mm wide radiator is the closest available standard size and will very likely be the perfect fit. The 420mm pipe centres suit the vast majority of standard UK central heating pipework. Need something wider? See our 1800 x 540mm version (4,309 BTU).

Useful information

5 Year Guarantee

Covered by Kartell UK against all manufacturing defects. One of the strongest guarantees available at this price point.

Free Delivery

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

Returns Policy

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

Complete Your Install

Valves sold separately. We also stock pipe covers, bleed keys, and inhibitor fluid. 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 you are completely satisfied.

Full Technical Specification
SpecificationDetail
Product NameKartell K-Rad Aspen Vertical Radiator 1800 x 420mm Single White
SKUASP18-43VSW
EAN / GTIN-135055681407445
Height1800mm
Width420mm
Depth55mm
OrientationVertical
Colour / finishGloss White
MaterialMild Steel
StyleOval tube — Modern
BTU output (Delta T60)3,368 BTU
Watt output (Delta T60)987W
BTU output (Delta T50)2,657 BTU (approx)
Heat pump compatibleYes
Fuel typeCentral heating (gas, oil, or electric)
Pipe centres420mm
Wall to pipe centres51mm
Valve connection1/2 inch BSP
Empty weight16.8kg
Max working pressure7.8 bar
Fixings suppliedYes — all fixings included
Manufacturer guarantee5 years — Kartell UK
ValvesNot included — sold separately (see Valves tab)
Which room size does this suit?
At 3,368 BTU (987W) this radiator comfortably heats rooms of approximately 42-52 sq ft — ideal for a large bathroom, single bedroom, or hallway. For larger or poorly insulated rooms, consider a wider size. Use the BTU Calculator tab for a precise recommendation based on your specific room dimensions.
Available sizes — Kartell K-Rad Aspen Single White Vertical Radiator
Cannot find your exact size? The 1800 x 420mm is the closest standard size to 1800 x 400mm, 410mm, 415mm, 425mm, 430mm, 440mm or 450mm. Radiators are manufactured in standard widths only.
Size (H x W) BTU (Delta T60) Watts Pipe Centres SKU
1800 x 300mm 2,392701W300mmASP18-31VSW
1800 x 420mm THIS PRODUCT 3,368987W420mmASP18-43VSW
1800 x 540mm 4,3091,263W540mmASP18-55VSW

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 420mm — 3,368 BTU at Delta T60
At 3,368 BTU, this radiator suits rooms of approximately 42-52 sq ft in a well-insulated modern property — a typical large bathroom, single bedroom, or hallway. For older or poorly insulated properties, allow for a smaller coverage area. 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.
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 (typically flow 80°C, return 60°C, room 20°C). Most modern combi boilers run at or near these temperatures. If your system runs cooler, the actual output will be lower.

Heat pump users: Heat pumps typically run at lower flow temperatures (35-55°C). At Delta T50, multiply the BTU figure by 0.789 — giving approximately 2,657 BTU for this radiator. At Delta T41, multiply by 0.638 — giving approximately 2,149 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 centres420mm
Wall to pipe centres51mm
Wall projection55mm
Valve connection1/2 inch BSP — angled, straight, or corner valves
Max working pressure7.8 bar
Compatible systemsSealed and open vented — gas, oil, electric, heat pump
Fixings suppliedYes — wall brackets, screws, plugs, air vent, blanking plug
ValvesNot included — see Valves tab

Heat pump compatible: At Delta T50 flow temperatures, output is approximately 2,657 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 with this radiator and must be purchased separately. This radiator uses standard 1/2 inch BSP connections. Select your pipework configuration below to find the right valve type.

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 valve type you need, angled valves are the most likely correct choice.

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. If replacing an existing radiator, match the type already fitted.
Angled valves available 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 the correct valve for your installation.

Straight Radiator Valves

When to use: Pipework rises vertically from the floor and connects directly to the bottom tappings of the radiator without turning.

Used where the pipework exits the floor directly beneath the radiator and the valve connects in a straight vertical line.

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

If you are replacing an existing radiator with straight valves already fitted, straight valves are the correct choice.
Straight valves available at PlumbXtra
Design Twin Pack TRV — White Straight
White finish — Straight — TRV + Lockshield
Design Twin Pack TRV — Chrome Straight
Chrome finish — Straight — TRV + Lockshield
Not sure? Call 01282 429061 — our team will advise the correct valve for your installation.

Corner Radiator Valves

When to use: Pipework comes horizontally out of the wall and connects to the side connections of the radiator. The corner valve redirects the wall pipe to the radiator.

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

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 based on your pipework.

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

Frequently asked questions — Kartell K-Rad Aspen 1800 x 420mm White
With 3,368 BTU (987W) at Delta T60, this radiator suits rooms of approximately 42-52 square feet. Use the BTU Calculator tab for a personalised calculation based on your exact room dimensions, insulation level, and glazing type.
Pipe centres are 420mm, 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 — this radiator comes with a 5 year manufacturer guarantee from Kartell UK, covering all manufacturing defects from date of purchase. One of the strongest guarantees available 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 lower heat pump flow temperatures the BTU output will be lower than the quoted Delta T60 figure — see the BTU Calculator tab for heat pump output estimates.
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 testing radiator heat output — it assumes a mean water temperature 60°C above the room air temperature. Most UK combi boilers operate at or near this standard. For Delta T50, multiply the BTU by 0.789 — giving approximately 2,657 BTU for this radiator. Use the BTU Calculator tab for further detail.
The Kartell K-Rad Aspen projects just 55mm from the wall — one of the slimmest profiles available for a designer vertical radiator of this output. The wall to pipe centres measurement is 51mm, making it suitable for most standard UK installations.
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.
Yes — the K-Rad Aspen 1800 x 420mm is one of the most popular hallway radiators in the UK. Its 420mm width fits neatly on even the narrowest hallway walls, and at just 55mm deep it will not obstruct foot traffic. The 1800mm height maximises heat output without requiring wide horizontal wall space.
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.

The Kartell K-Rad Aspen is one of the UK's best-selling designer vertical radiators — available from PlumbXtra with free delivery on orders over £500. Also searched for as: Kartell Aspen white 1800x420, K-Rad Aspen 1800 x 420mm white, Aspen vertical radiator white 1800mm, designer vertical radiator white 1800x420mm, 1800 x 400mm vertical radiator, 1800 x 410mm vertical radiator, 1800 x 415mm vertical radiator, 1800 x 425mm vertical radiator, 1800 x 430mm vertical radiator, 1800 x 440mm vertical radiator, 1800 x 450mm vertical radiator, 1800 x 460mm vertical radiator, 1800 x 470mm vertical radiator, 1800 x 480mm vertical radiator, oval tube white vertical radiator, ASP18-43VSW, Kartell radiator 1800x420 white, K-Rad vertical radiator white 1800mm, hallway radiator white 1800mm.

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