Oil Filled Radiator vs Convection Heater: Factory Truth

Every week a buyer asks me which one they should stock: oil filled radiator vs convection heater. The honest answer is that they solve different problems. Pick wrong and you'll get returns, bad reviews, and a container of dead stock. Here's what I tell them after 15 years on the line.

How they actually work

A convection heater is simple. A metal fin or element gets hot, air rises off it, cool air replaces it. That's it. No fluid, no pressure, no warm-up lag. A 2000W panel starts pushing heat in about 30 seconds.

An oil filled radiator has a sealed steel body filled with thermal oil. The element heats the oil, the oil heats the fins, the fins heat the room. That takes 10 to 15 minutes to feel warm. But when the thermostat cuts power, the oil keeps giving heat for another 20 to 30 minutes. That's the whole difference in one paragraph.

Where convection wins

If your customer needs fast heat in a room they use in bursts, convection is the better sell. Bathrooms, workshops, offices. A wall mounted electric heater with a 1500W element and a decent thermostat is cheap to build, cheap to ship, and cheap to run because there's no oil mass to keep hot.

Convection panels are also the right call for a low wattage electric heater strategy. A 400W or 600W panel won't heat a garage in January, but it will take the chill off a bedroom overnight without tripping a 10A breaker. That's a real market: people who want background heat, not blast heat.

Downside: convection dries air out faster and the surface gets hot enough to matter. If you're selling into markets with kids or pets, you need a certified tilt switch and overheat cutout. Don't skip that to save 40 cents.

Where oil filled wins

Oil filled radiators are the quiet workhorse. Zero fan noise, zero clicks, zero airflow. If a buyer searches for a silent electric heater, this is the product you quote them. They're heavy — a 2000W unit runs 9 to 12 kg — so freight cost per unit is higher. That kills margin on cheap SKUs. But the perceived value is higher too. Consumers see fins and weight and think "real heater."

They also hold temperature better in a large room. If someone wants an electric heater for large room use and doesn't want a fan blowing dust around, oil filled is the answer. Same for a bedroom where the thermostat clicking on and off all night would wake them.

One warning: oil filled units are not for bathrooms unless you've done the IP rating work. Most aren't IP24. Don't let a buyer talk you into listing one as a bathroom heater. That's how you get a recall.

The cost question buyers always ask

Both types convert electricity to heat at roughly 100% efficiency. A 2000W heater costs the same to run as any other 2000W heater at the meter. The savings come from how you control it.

A thermostat that actually reads room temperature, not just element temperature, is worth more than any heating technology. We've tested it: a 1500W oil filled radiator with a proper electronic thermostat cycling at 50% duty costs about half of a 1500W convection panel left on full. Same wattage, different control. That's the number you should put in your listing, not vague "energy efficient" claims.

If you're sourcing for a market with high electricity prices, spec a 7-day programmable thermostat. It adds maybe $3 to your landed cost and it's the difference between a 3-star and a 4.5-star review.

What to actually stock

If you're a distributor building a range, don't pick one. Stock both.

• Entry SKU: 1500W convection panel, wall mounted, mechanical thermostat. Low cost, low freight, good for bathrooms and small rooms.
• Mid SKU: 2000W oil filled radiator with 3 heat settings and a timer. This is your volume seller in colder markets.
• Premium SKU: wifi smart electric heater, either type, with app control and scheduling. Sells to the Amazon crowd who want to turn it on from the car.

MOQ on most of our models is 200 pcs per SKU. Lead time runs 15 to 45 days depending on whether you need custom packaging, a private label electric heater program, or just a stock unit with your logo. Certifications matter more than price here: CE, RoHS, UKCA, and ERP Lot 20 compliance are non-negotiable for EU and UK. If a supplier can't show you those before you ask, walk.

One honest takeaway

The oil filled radiator vs convection heater debate isn't about which is better. It's about which customer you're selling to. Fast heat and low cost go convection. Silent, steady, high perceived value go oil filled. If you can't decide, buy 200 of each, run them for a season, and let your own returns data tell you. That beats any spec sheet I can send you.