Oil Filled Radiator vs Convection Heater: A Factory Comparison

We've been building both oil-filled radiators and convection panels on the same floor since 2009. Buyers ask me which one to stock every week. The honest answer: it depends on who's buying and what they complain about after the first winter.

How they actually heat a room

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 fast. A 2000W wall-mounted panel can make a small office feel warm in 10 minutes. But kill the power and the warmth goes with it.

An oil-filled radiator works differently. The element heats diathermic oil inside sealed fins. The metal body becomes the heat source. It takes 20–30 minutes to get going, but it keeps radiating for another 20–30 minutes after you switch it off. That lag matters. For a bedroom, that slow release is the whole point. For a garage where you're working for two hours, it's wasted.

Noise and the silent electric heater question

Neither design has a fan, so both are silent. That's a real selling point. The only noise from an oil radiator is the occasional tick of expanding metal. If a buyer searches for a silent electric heater for a nursery or a home office, either type qualifies. Don't let a competitor tell you otherwise. The fan heaters we build for industrial use are a different animal entirely.

Running cost: the number that decides reorders

Here's the blunt math. A 2000W heater running flat out for 8 hours uses 16 kWh. At $0.15/kWh that's $2.40 a day, roughly $72 a month. A 1500W unit on the same schedule is $54. The difference between oil and convection isn't wattage, it's duty cycle. Oil radiators cycle on and off more once the room is at temperature, so real-world consumption is often 15–25% lower than a convection panel of the same rating. That's why "cheap to run electric heater" searches spike in January. Buyers aren't stupid. They've seen the bill.

If your market compares electric heater vs gas, be careful. Gas is still cheaper per kWh in most regions. The electric pitch is installation cost and no flue, not fuel price.

Where each type wins

Oil-filled radiators: bedrooms, basements, bathrooms with the right IP rating, anywhere you want residual heat. Heavy. A 2000W unit ships at 11–13 kg. That freight cost hits your landed price.

Convection panels: wall-mounted electric heater applications, offices, hallways, rental flats where floor space is tight. Light, cheap to ship, fast to warm. A 2000W panel is often under 4 kg.

For a large room, neither a single 2000W oil radiator nor a single panel will do it. You need 100W per square meter as a rough rule. A 30 m² room needs 3000W, so two units or a 3000W model. Tell your customers that before they leave a one-star review saying "doesn't heat my living room."

What buyers get wrong on specs

Thermostats. A mechanical bimetal thermostat swings 3–4°C. A digital thermostat holds 1°C. If you're pitching a best electric heater with thermostat angle, digital is the story. It's also the feature that justifies a higher retail price.

WiFi. A wifi smart electric heater adds maybe $6–9 to our BOM at 500 pcs. It's the easiest upsell in this category. But the app has to work. We've seen brands launch with a white-label app that crashes and get buried in returns.

IP ratings. Bathroom units need IP24 minimum. Don't let a buyer put a standard panel in a bathroom and call it done. That's a liability claim waiting to happen.

Certifications and sourcing reality

For Europe you need CE, RoHS, and ERP compliance. ERP sets the standby power limit, currently 0.5W for most units. UKCA is separate for the UK now. For North America, ETL or UL. We hold these on our standard platforms, but a private label electric heater with a custom housing means new testing. Budget 3–4 weeks and a few thousand dollars.

MOQ is 200 pcs for standard models. Custom colors or housing changes push it to 500. Lead time runs 15–45 days depending on whether you're taking stock or a full OEM run. If you need units for a Q4 Amazon push, place the order by July. Every year someone tries in September and pays air freight.

The takeaway

Stock oil-filled radiators for customers who want quiet, steady, residual heat and don't mind the weight. Stock convection panels for fast heat, low freight, and wall-mount applications. Don't try to sell one as a universal answer. The buyers who get burned are the ones who promise a 1500W panel will heat a 40 m² open-plan space. Match the wattage to the room, match the type to the use case, and your return rate stays under 3%. That's the whole game.