Oil Filled Radiator vs Convection Heater: What to Source

You're sourcing heaters for a market that's already split between two technologies, and if you pick wrong, you'll be stuck with a container of units that move slow. I've been on the production floor since 2009, and I've seen both oil filled radiators and convection panels leave our plant in roughly equal numbers. They're not interchangeable, and the buyers who treat them that way end up with returns and chargebacks.

Let me walk you through what actually matters when you're deciding which one to put your private label on. This isn't a marketing comparison. This is what we tell our own procurement partners when they ask.

Heat Up Speed and Comfort

An oil filled radiator heats oil inside sealed fins, then that oil heats the metal, then the metal radiates heat into the room. That takes time. From a cold start, expect 15 to 20 minutes before you feel real warmth. But once it's hot, it stays hot. The oil holds heat and keeps emitting it even after the thermostat cycles the element off. That's why these units feel steady and don't blast you with hot air.

A convection heater works differently. It pulls cool air from the bottom, passes it over a heating element, and pushes warm air out the top. The room heats up faster, usually within 5 to 10 minutes. But the moment you switch it off, the heat stops. No thermal mass. For a buyer's customer, that means the oil filled radiator is better for a bedroom where you want consistent overnight warmth, while the convection panel wins in an office or a living room where you're popping in and out and want quick comfort.

If you're sourcing for a market with cold winters and drafty houses, the oil filled radiator has a reputation for feeling less "dry" and more like old-school central heating. That's a selling point you can use.

Running Cost and Energy Efficiency

Here's where a lot of marketing fluff dies. Both technologies are roughly 100% efficient at converting electricity to heat. Every watt you put in becomes heat. So the real difference in running cost comes down to thermostat accuracy and how well the unit holds a set temperature.

Our oil filled radiators use a mechanical bimetallic thermostat that can drift by 2 to 3 degrees. That means the element cycles on and off less precisely, and you can overshoot the target temperature. Our convection panels use a digital thermostat with a sensor that's accurate to about 0.5 degrees. Over a heating season, that can shave 8 to 12% off the electricity bill for a typical 20 square meter room. That's the difference between a 1500W unit running 30% of the time versus 35% of the time.

If you're marketing to customers who search for an "energy efficient electric heater" or a "low wattage electric heater," the convection panel with a digital thermostat is the honest answer. But if your customer wants a unit that holds heat and doesn't cycle as often, the oil filled radiator's thermal mass does that naturally, even with a less precise thermostat.

Safety and Certifications

Both types can be made safe, but they have different failure modes. An oil filled radiator has a sealed oil circuit. If the element fails, you get a leak, not a fire. That's a big deal for bedrooms and for anyone with kids or pets. We always fit a thermal cutout and a tip-over switch on our oil filled models. That's standard.

A convection heater has an exposed element behind a grille. If a customer blocks the inlet or outlet, the internal temperature can spike. We build in a thermal fuse that cuts power at 180°C, and we test every unit for surface temperature limits. For bathroom use, you need IP24 protection, which means the unit is splash-proof from all directions. We only offer that on our convection panels, not on oil filled radiators, because the fins are too hard to seal properly.

If you're sourcing for a market that requires CE or UKCA, make sure your supplier actually tests to the latest standard. We've seen cheap imports with fake CE marks. Our units are tested to EN 60335-1 and EN 60335-2-30, and we provide the test reports on request. That's not a sales pitch, it's a liability issue.

Weight, Mounting, and Space

Oil filled radiators are heavy. A 2000W model weighs around 15 to 18 kg, mostly oil and steel. They come with castors, but they're not something you wall mount. They take up floor space, and they're awkward to ship. That's fine for a permanent spot in a living room, but not for a small apartment or a garage where floor space is tight.

Convection panels are light. A 2000W wall mounted model weighs about 5 to 6 kg. You can hang it on a standard drywall anchor. That's a huge advantage for customers searching for a "wall mounted electric heater" for a bedroom or a workshop. It also means lower shipping cost per unit, which directly affects your landed cost.

For a garage or a basement, I'd lean toward a convection panel with a high IP rating and a fan-assisted option. A plain convection panel will heat a 30 square meter garage, but it'll take longer because there's no air movement. We make a 3000W fan-forced convection unit for that exact use case, and it's one of our best sellers for industrial buyers.

Real Comparison Number

Let's put it this way. For a 20 square meter bedroom with average insulation, a 1500W oil filled radiator will run about 35% of the time over a 24-hour period to hold 20°C when it's 0°C outside. That's 12.6 kWh per day. A 1500W convection panel with a digital thermostat will run about 28% of the time, so 10.1 kWh per day. At $0.15 per kWh, that's $0.38 per day difference. Over a 150-day heating season, that's $57 per unit. If you're selling 1000 units a year, that's a $57,000 difference in your customer's pockets. That's why the thermostat matters.

But the oil filled radiator will still sell. It's quieter, it doesn't blow dust, and it feels more "solid" to a certain type of buyer. There's a reason people still search for "silent electric heater" and end up buying an oil filled model.

Sourcing Reality

If you're going the OEM route with a Chinese manufacturer, be ready for MOQs. Our standard MOQ is 200 pcs per model, and lead time is 15 to 45 days depending on the configuration and whether we need to order custom packaging. If you want a custom color or a specific thermostat brand, that adds 7 to 10 days. If you want a wifi smart electric heater with app control, that's a different PCB and a longer lead time, usually 30 to 45 days.

Don't ask for a sample of one and then expect a 5000-unit price. That's a rookie move. Ask for the test report, the BOM, and the exact thermostat brand. Then ask for a pre-production sample at 200 units. That's how you avoid a bad batch.

The Honest Takeaway

Oil filled radiators are for comfort and steady heat. Convection panels are for speed, control, and wall mounting. If you're sourcing for a broad retail line, carry both. If you're sourcing for a specific use case, pick based on the room and the customer's electricity price. Don't let a supplier talk you into one because it's cheaper to make. The cost difference is pennies on the unit, but the returns and bad reviews will cost you real money.

And if you're sourcing from us, we'll tell you the same thing. We make both. We'd rather you order the right one and come back for more.