Oil Filled Radiator vs Convection Heater: What to Source

If you're sourcing heaters for a market that gets cold and stays cold, you've probably stared at two options on the factory spec sheet: oil filled radiators and wall mounted convection panels. Both sell. Both have loyal followings. But they are not interchangeable, and picking wrong means returns, complaints, and a dead product line.

I've been on the production floor since 2009, and I've seen buyers burn money on the wrong type for their region. Let's cut through the marketing noise and talk about what actually matters when you're deciding what to put in your container.

How Each One Actually Heats

An oil filled radiator heats oil inside a sealed metal fin. That oil holds heat long after the element cycles off. The surface gets hot—usually 80-110°C—and it heats by radiation and natural convection. It's slow to warm up, but it keeps a room stable.

A convection panel pulls cold air from the bottom, runs it over a heating element, and pushes warm air out the top. No oil, no thermal mass. It heats the air directly and cycles on and off as the thermostat reads the room. Warm-up is faster, but the heat disappears as soon as the unit switches off.

That's the core difference. One stores heat, the other doesn't. Everything else—price, weight, mounting—flows from that.

Real Numbers You Can Use

Let's talk watts, because that's what your customers actually ask about. A typical 1500W oil filled radiator covers roughly 150-200 square feet (14-18 m²) of a well-insulated room. A 1500W convection panel does the same, but it will cycle more often because it doesn't have thermal mass.

For a large garage or workshop with poor insulation, neither 1500W unit will cut it. You need 2000-2500W, and an oil filled unit will hold the temperature better when the door opens and closes. For a bedroom, a 500-700W convection panel on a timer is often enough, and it won't bake the room.

Efficiency is a trap. Both are nearly 100% efficient at converting electricity to heat. The difference is how the heat feels and how long it lasts. An oil filled radiator at 1500W costs the same to run as a convection panel at 1500W. But the oil filled unit will keep the room warm longer after the thermostat cuts out, so in practice it can be cheaper to run in a space that needs constant heat.

What Buyers Search For and Why

I've seen the search data from our distributors. The two big queries are "oil filled radiator vs convection heater" and "wall mounted electric heater." That tells me buyers are comparing, and they want to know which one fits their shelf and their customer.

Here's the blunt truth: convection panels are easier to ship, easier to install, and cheaper to land at retail. They're flat, lightweight, and mount on a wall, which saves floor space. That's why they dominate in Europe and the UK, where apartments are small and wall space is available.

Oil filled radiators are heavier, bulkier, and usually come with castors. Shipping costs more. But they're the safer bet for a living room or a bedroom where a customer wants silent, draught-free heat and doesn't mind the footprint. They also run cooler on the surface than some convection panels, which matters for homes with kids or pets.

The Bathroom and Safety Question

If your target market is bathroom heating, you need IP24 rating. Both types can be built to that spec, but a wall mounted convection panel is the obvious choice—it doesn't take floor space, and it can be installed above a towel rail without blocking a doorway. Oil filled radiators are usually floor-standing, and most customers don't want that in a small bathroom.

For a silent electric heater, both work. Oil filled radiators have no fan, so they're silent except for occasional clicking from the thermostat. Convection panels are also silent, but some cheaper models have a relay that clicks loudly on cycling. If you're sourcing for a bedroom, test that relay. It's a common complaint.

What About Smart and WiFi?

Buyers increasingly ask for "wifi smart electric heater." We can build that into either type. But remember: smart features add cost and a failure point. If your customer just wants a thermostat and a timer, don't push smart. If they're on Amazon and want to compete on features, then add it. Just know that the return rate on smart heaters is higher than on dumb ones, mostly because of app pairing issues.

Manufacturing Reality Check

As a factory, we make both. Our standard MOQ is 200 pcs per model, and lead time is 15-45 days depending on the finish and whether we need to source new tooling. Oil filled radiators require a radiator body from a steel supplier, which adds 10-15 days to lead time. Convection panels are faster to assemble because the body is stamped aluminum or steel and the heating element is simpler.

Certification is non-negotiable. For Europe, you need CE and RoHS. For the UK, UKCA. For energy labeling, ERP. If you're sourcing for a specific country, confirm the certs before you sign. We've seen buyers get stuck with a container that can't clear customs because they didn't check the ERP energy class.

One Honest Takeaway

Don't pick a heater type based on what's trendy. Pick based on your customer's room size, insulation, and how they use the space. If they want steady, long-lasting heat in a living room, oil filled. If they want fast heat in a small room or a bathroom, convection. And if you're not sure, order samples of both, run them in a real room, and measure the temperature drop after the thermostat cycles. That data will tell you more than any spec sheet.

Your margin depends on getting this right the first time. Get it wrong, and you'll be sitting on a container of returns. Get it right, and you'll have a steady reorder product for years.