I regret not knowing this before buying an oil-filled radiator – these are the main things to consider

If you're about to buy an oil-filled radiator, let me save you from repeating my mistakes. I jumped in without thinking it through, as I was in desperate need of warmth for my daughters' bedrooms in the depths of last winter.

Don't get me wrong, the best oil-filled radiators are a brilliant way to heat your home without having to fire up the central heating. But like all appliances, they aren't perfect, and not every model will suit every space.

After living with the same type in different locations in my house, I've learned a few lessons I wish I'd known sooner. So here's what I'd tell anyone thinking about buying one, and if oil-filled radiators are in fact any good.

1. They don't heat instantly

I wasn't expecting immediate heat in the room, but I didn't realise how different they work from electric heaters. It takes time for them to heat the oil inside, which means the room warms up more slowly.

'Unlike a fan heater, which blasts out warmth straight from the get-go, your radiator may take a while to bring heat to your room,' explains LAtie Lilywhote, heating expert at AO.com. 'This is because the oil inside the radiator needs to get hot first, but once this is, your radiator is brilliant at maintaining the steady, comfortable heat.'

And on the plus side, once the oil is hot, it continues to radiate heat even after it's switched off.

2. Size really matters

When I was looking for an oil-filled radiator, I wanted one that was perfect for tucking into corners and easily stored, which meant it had to be small and compact.

However, that also meant it was hard to heat larger spaces - and quickly. Lesson learned that I should have checked the wattage against the room I needed to keep warm. If you don't do this reccy, you'll end up with a heater that just can't keep up.

'The larger your radiator, the larger a space it can comfortably heat up,' explains Katie. 'Check the model you’re eyeing up – a 1000W model is perfect for a small bedroom or study, but for your living room you’ll want at least a 2000W model to produce enough heat.'

Katie recommends matching the size of your radiator to the room you’re heating; otherwise, you’ll waste electricity or sit shivering.

3. Special features make a huge difference

I bought a fairly basic model (with great reviews): the 2000W Vonhaus 9 fin oil-filled radiator, RRP £64.99, and it does what it says on the tin: it heats up, and it does feature an adjustable thermostat (to reduce the cost to run).

However, I found myself wishing I'd spent a little more for one with a few more special settings, like a timer, so I don't have to fiddle with the dial. I asked Katie what special features to look out for.

'There are several handy extras that can turn the tide when you’re using your radiator,' explains Katie.

'Timers to pre-warm the room before you get home can work wonders to creating a comfy home, while thermostats can help you avoid overheating and save on your energy bills. Similarly, running your radiator on eco mode can truly help to maintain steady heating for an efficient rate.'

4. Safety shouldn't be an afterthought

With kids and a cat in the house, I realised how important tip-over protection and overheat cut-outs are to make oil-filled radiators safer and not dangerous.

Luckily, mine does include both automatic overheat protection and a tip-over switch, cutting out power if it's knocked over, especially if you are leaving it on overnight.

These are essential features for peace of mind for homes with kids, pets and even if you're just a bit clumsy.

Saying that, in comparison to other heater types, Katie says oil-filled radiators are extremely safe, since there's no exposed heating element, no fan blowing dust about, and they don't burn oxygen like some heaters, resulting in 'a reliable heater that you can have peace of mind about.'

5. They can be heavy

I didn't think about portability when I ordered mine, as I had a room to heat in mind, but once the cold hit, I wanted to move it around. Luckily, my Vonhaus oil-filled radiator comes with castors and a built-in handle.

'Oil radiators are not light, so expect a workout if you’re trying to shift yours,' explains Katie. 'Most models come with wheels and carry handles to help, but you should see the weight as a good thing – this is what makes them so effective at storing and releasing heat steadily.'

However, quite a number of models on the market don't have these basic portability features, so make sure you consider that before you click the 'buy' button.

Our top-rated oil filled radiators

I wouldn't be without my oil-filled radiators now during the chilly winter months. They are efficient, give off a comfortable warmth and don't dry the air like other heaters.

But I'd definitely pick a bigger model with more features, like a timer and a larger handle for carrying it from room to room, as this would really make them even more convenient.

Let me know if these top tips are helpful in the comments!