De'Longhi Dragon 4 Oil-Filled Radiator review: "amazing for heating a room"

Price on writing: £170 | Buy now from Amazon

How I tested

I tested the De'Longhi Dragon 4 at home over the course of six weeks in autumn 2025. I tried it under a desk and to heat my 19m² sitting room, using an infrared thermometer gun to take accurate temperature readings from the middle of the room. Taking detailed notes on energy-efficiency, user-friendliness and how well it heats up a room, I scored it against a number of criteria and compared it to similar products, as well as alternative sources of heat such as heated throws.

Read next: Best electric heaters

De'Longhi Dragon 4 Oil Filled Radiator: my verdict

• Performance: 15/15

• Quality and durability: 15/15

• Ease of use: 11/15

• Value for money: 12/15

• Energy efficiency: 7/10

• Heat distribution: 10/10

• Warmth: 10/10

• Storage: 7/10

• Total: 87/100

First things first: this oil-filled radiator is amazing for heating a room. Suitable for rooms up to roughly 30m², it warmed up my 19m² sitting room an absolute treat, with a noticeable difference in the room temperature within 10 minutes of turning the radiator on.

The radiator's unique chimney design is what makes it so effective at heating up a large room. Pushing warm air upwards through vents in the top of the radiator, it quickly raises the temperature of the room. Using an infrared thermometer gun, I measured an increase from 16°C to 18°C after an hour with the integrated thermostat set to max (28°C).

However, this design makes it quite different to regular oil-filled radiators, which radiate heat from their sides rather than pushing out hot air. I like to have an oil-filled radiator under my WFH desk to avoid heating the whole house while it's just me at home, and the size and design of the Dragon 4 meant it wasn't suitable for this - the chimney function is stifled by being squeezed under a desk. Admittedly, it easily warmed up my study when placed in a different position, but space is at a premium in this room, so if it doesn't fit under the desk it's less practical.

Instead, it came into its own in the sitting room, where it heats up the space quickly, making it wonderfully warm and cosy for relaxing in at the end of the day.

With flexible swivel castors, the radiator is easy to move around, and has heat-proof handles to make manoeuvring it into the perfect spot simple and fuss-free. At 1.38m, the power cord felt slightly short, but it does wind away neatly on the radiator for storage.

At 2.5kW, the De'Longhi Dragon 4 is quite a powerful beast, and costs roughly 37 to 85p per hour to run, depending on the setting you use. Compared to a heated throw like the Dreamland Alaskan Husky Heated Blanket, which costs less than 5p per hour, the Dragon 4 is quite expensive to run.

However, the Dragon 4 is designed to heat a whole room, rather than just one person. It does more than a standard radiator, so you'll need it on for less time to achieve the same results - and its oil-filled design means it cools down slowly, continuing to heat the room after it's switched off.

It also comes with a smart ECO mode, which selects the optimal power level to heat the room most efficiently. There's a timer function so you can set the radiator to turn on and off at set times each day, and of course a thermostat so it turns off once it reaches the target temperature.

The timer function is complex to set up initially, as it uses only a dial and time button to toggle through settings, with no digital display. A word to the wise: keep hold of the instruction booklet for this one to get the most out of it.

All in all, this is a brilliant and powerful radiator that goes above and beyond to heat a whole room up. If you're looking for ways to reduce your central heating bill but still want a warm room, it's the best in the business.

Is the De'Longhi Dragon 4 good for heating a room?

It's amazing at heating a room quickly. Better and faster than the two regular radiators in my sitting room, in fact. This is due to the Dragon 4's 'chimney' design, which funnels warm air up and out of the top of the radiator, as well as radiating heat from its sides like a regular oil-filled radiator does.

If your boiler breaks down, this is the emergency back-up to have on hand. It provides both fast and long-lasting heat for a whole room, up to 30m². However, its powerful 2.5kW output comes at a cost - between 37p and 85p per hour, so if you have a small home it's worth checking how much your central heating costs to run before buying.

Is the De'Longhi Dragon 4 good value for money?

At £170 (at the time of writing), this is a really powerful and efficient radiator for heating up a room. The oil-filled design means it'll hold onto its heat for longer than a fan or halogen heater, and its thermostat and timer mean you can tailor it to your routine so you're using it in a smart way.

However, if you're looking for the cheapest way to stay warm without turning on the central heating, you're better off with a heated blanket or heated gilet, which are designed to heat the human, not the room.

If you want to warm one room, a convector heater like this one from Daewoo is the cheapest option, but it'll take longer to heat up than the De'Longhi Dragon 4.

In short, the Dragon 4 is the best around when it comes to performance, but there are cheaper options out there - both in terms of upfront cost and energy usage. If you're looking for a quick, reliable and effective radiator with modern energy-saving features, the Dragon 4 is an excellent investment.

About the author

Poppy O'Neill is a Content Editor at Mumsnet and a mother of two. She researches and reviews the products Mumsnetters swear by, with a particular focus on laundry essentials like steam irons, clothes steamers and washing lines.

From a highly recommended retractable washing line to the best quiet fans money can buy, and Mumsnet's favourite dehumidifier to the steam generator iron that'll cut your ironing time in half, she loves to deep-dive into research and find the very best products on the market.