Oil-Filled Radiator vs Convection Heater: Factory Comparison

Most buyers ask me the same thing: which one sells better, oil-filled or convection? My answer is always the same. Depends on your market. Depends on your price point. And depends on whether your customers care more about silence or speed. I've run both lines since 2009. Here's what actually matters.

How they heat is completely different

Oil-filled radiators work by heating diathermic oil inside sealed fins. The oil holds heat. When the thermostat clicks off, the unit keeps radiating for 10–15 minutes. That's why people call them a silent electric heater. No fan, no click, no airflow. Just steady warmth.

Convection heaters pull cold air in the bottom, run it over a finned element, and push it out the top. Faster heat-up. But when the thermostat cuts, the warmth stops almost immediately. You feel the difference in a drafty room.

For a bedroom, oil-filled wins almost every time. For a workshop where you need heat now, convection wins.

Wattage and room size: the numbers buyers get wrong

A common mistake: assuming a 2000W heater heats any room. It doesn't. Rule of thumb for well-insulated spaces is 10W per square foot. A 2000W unit handles roughly 200 sq ft. For an electric heater for large room use, you need 2500W or two units.

We build most oil-filled units at 1500W and 2000W. Convection panels at 1000W, 1500W, 2000W. A low wattage electric heater at 500W or 750W is fine for a bathroom or small office, but don't sell it as a main heat source.

If your customer asks about an electric heater for garage, be honest. Most garages are poorly insulated. A 2000W convection unit might hold 55°F on a 20°F day. That's it.

Wall mounted vs portable: what your buyers actually want

Wall mounted electric heater units sell well in Europe. UK, Germany, France. They save floor space and look permanent. But installation matters. A 2000W wall panel needs a dedicated circuit in some older homes. Your product listing has to say that. Otherwise you get returns.

Portable oil-filled radiators with casters sell better on Amazon in the US. Easier to return, easier to move. But shipping weight kills margin. A 2000W oil-filled unit weighs 22–28 lbs. A convection heater at the same wattage weighs 6–9 lbs. That's a real freight difference at 200 pcs MOQ.

The thermostat question

Every buyer wants a best electric heater with thermostat. Fine. But there's a catch. Mechanical thermostats are cheap and reliable. Digital thermostats cost more but hold temperature within 1–2°F. For a wifi smart electric heater, you're adding a module that costs us about $4–6 per unit at scale. That's fine for private label electric heater brands selling at $89+. Not fine for a $29 commodity unit.

We've seen buyers try to hit a $39 retail price with wifi. It doesn't work. The module alone eats the margin.

Safety and certifications: don't skip this

CE and RoHS are baseline for Europe. UKCA for UK. ERP lot 20 applies to local space heaters sold in the EU. If your supplier can't show you an ERP test report, walk away. We test every batch for tip-over switch, overheat protection, and thermal cut-out.

For bathroom use, IP24 is the minimum. An electric heater for bathroom IP24 means splash-proof, not waterproof. Don't let your listing say otherwise.

Oil-filled vs convection: running cost reality

Both types convert electricity to heat at nearly 100% efficiency. A 1500W heater costs the same to run whether it's oil-filled or convection. The difference is how long the thermostat stays on. Oil-filled units cycle less because the oil holds heat. In a small, insulated room, that can mean 10–15% less runtime. In a large, drafty space, the advantage disappears.

Electric heater vs gas is a different conversation. Gas is cheaper per BTU in most markets. But electric wins on installation cost and room-level control. Your buyers already know this. Don't oversell.

What I'd actually stock

If you're a distributor deciding what to source, here's my honest take. Carry one oil-filled line at 1500W and 2000W for bedrooms and offices. Carry one convection line at 2000W for workshops and garages. Add a 500W low wattage electric heater for bathrooms and small spaces. Skip the 12V electric heater for RV campervan unless you have a niche buyer. That market is small and price-sensitive.

MOQ is 200 pcs per model. Lead time runs 15–45 days depending on whether you need custom packaging or a private label electric heater program. Certifications add 5–7 days if we're testing a new design.

The takeaway: oil-filled and convection heaters solve different problems. Neither is universally better. If you stock only one, you're leaving money on the table. If you stock both, you need to train your sales team on when to recommend each. That's the real work.