Oil-Filled Radiator vs Convection Heater: Which to Source?

I've watched buyers stand in our showroom, stare at two heaters side by side, and ask the same question: which one actually sells? The oil-filled radiator and the convection panel look similar on a spec sheet. Both plug in. Both have a thermostat. But they behave differently in a room, and that difference decides which one your customer keeps and which one comes back as a return.

Let's cut through it.

How they actually heat

A convection heater pulls cold air in at the bottom, runs it over a finned element, and pushes warm air out the top. It heats the air. That air moves around the room. If you put your hand above it, you feel warmth in seconds. The downside: when you turn it off, the warmth goes away fast. The air cools, and the room drops back.

An oil-filled radiator heats the oil inside sealed columns first. The metal gets hot. The metal heats the air around it. It's slower to start, maybe 10 to 15 minutes before you feel real heat. But when you switch it off, those columns stay warm for another 20 to 30 minutes. It's a gentle, steady heat. No fan noise, no dry air rush.

For a bedroom, that slow release matters. People don't want a heater that blasts and stops. They want a silent electric heater that holds temperature overnight. Oil-filled wins there almost every time.

Where convection wins

Convection panels are cheap to build, light to ship, and respond fast. A 2000W wall mounted electric heater can take a cold office from 12°C to 20°C in under half an hour. That's why they dominate the office and workshop segment. If your buyer needs a heater for a large room that's occupied in bursts, convection is the practical pick.

They're also thinner. A 2000W panel might be 80mm deep. An oil-filled radiator with the same output is 250mm deep and weighs three times as much. That weight hits you twice: once in freight, once in the customer's hands when they move it.

The running cost question

Here's where buyers get confused. A 2000W heater is a 2000W heater. Whether it's oil or convection, it draws 2kWh per hour at full power. The difference is how often the thermostat cycles it off.

Oil-filled radiators hold heat, so the thermostat cuts power more often once the room is stable. In a well-insulated bedroom, a 1500W oil radiator might run at 60% duty cycle after the first hour. A convection heater in the same room might run at 75%. That's a real gap in electric heater running cost over a winter.

But in a drafty garage? The oil radiator never gets ahead. The convection heater at least throws heat where you're standing. So the answer depends on the room, not the product.

What to stock

If you're a distributor deciding what to source, don't pick one. Stock both, but position them differently.

Oil-filled radiators: sell them as bedroom and living room heaters. Push the silence, the steady heat, the fact that they keep warming after you switch off. A 1500W unit with 7 fins is the volume seller in Europe. MOQ 200 pcs, lead time 30 to 40 days.

Convection panels: sell them as wall-mounted space savers for offices, bathrooms, and workshops. The IP24 bathroom version is a steady niche. 2000W, CE and UKCA, 15 to 25 day lead time if you use our standard housing.

Infrared is a third option, but that's a different article. Short version: it heats objects, not air. Great for a workshop where you're standing still. Bad for a bedroom where you want the whole room warm.

The honest takeaway

There's no universal winner. If your market buys for bedrooms, oil-filled radiators earn better reviews and fewer returns. If your market buys for offices or quick heat, convection panels move faster and cost less to ship. The mistake is treating them as interchangeable. They're not. Ask your buyer what room the heater goes in. That one question tells you which container to book.