Oil Filled Radiator vs Convection Heater: What to Source

You're sourcing heaters for a market that's split between two technologies, and you need to know which one to bet on. I've watched buyers guess wrong on this and eat the cost. Let's settle it with numbers, not marketing.

Both oil filled radiators and convection panels do the same job: they warm a room. But they do it on different physics, and that changes everything about your product line, from shipping weight to return rates.

The core difference: radiant vs. airflow

An oil filled radiator heats oil inside a sealed metal fin. That oil holds heat and slowly radiates it out. A convection heater pulls cold air in at the bottom, heats it over an element, and pushes it out the top. No fan, just natural airflow.

That's it. Everything else is a consequence.

Heat-up time: the buyer's first complaint

Convection wins on speed. A 1500W convection panel will feel warm in your hand within two minutes. The air in a 12m² room starts moving noticeably in about five. An oil filled radiator at the same wattage takes fifteen to twenty minutes before you feel anything. The oil mass has to absorb heat first.

If your customer is someone who walks into a cold bedroom and wants it warm before they change clothes, convection is the answer. If they want a heater that runs all night and doesn't cycle on and off every few minutes, oil filled is better.

Running cost: the lazy metric that matters

Both are 100% efficient at converting electricity to heat. A 1500W convection heater and a 1500W oil filled radiator use the same electricity per hour. The difference is how long they run.

A convection heater heats a room fast, hits the thermostat set point, and cuts out. An oil filled radiator heats slowly, overshoots less, and holds a steadier temperature. In a well-insulated room, the oil filled unit will run less total time over eight hours. In a drafty room, convection will cycle more but still use roughly the same energy. Don't sell either as an energy efficient electric heater over the other. Sell them on behavior.

If you want a real low wattage electric heater for a small office, a 500W convection panel is a practical choice. It won't heat a large room, but it will keep a 6m² space comfortable without scaring the user with the bill.

Comfort: who feels the difference

Oil filled radiators heat surfaces, not just air. The wall behind the heater stays warm. The floor near it gets warm. That's why people describe it as a cozy heat. Convection heaters warm the air, which rises and collects near the ceiling. The floor stays cold in a high-ceiling room.

If you're sourcing for a garage or workshop where the user stands on concrete, oil filled is the better call. The radiant heat hits the body directly, even if the air is still cool. For a bedroom or office where the user sits at a desk, convection is fine and much quieter in terms of perceived drafts.

Silent operation: both pass, but differently

Neither makes fan noise. But convection heaters click when the thermostat cycles. Oil filled radiators can make a ticking sound as the oil expands and the metal case moves. In practice, buyers rarely complain about either. If you want a silent electric heater, look at the thermostat quality, not the heating technology. A cheap bimetal thermostat clicks loudly. A capillary thermostat with a slow switch is nearly silent.

Weight and shipping: the hidden cost

This is where many private label buyers trip. A 1500W oil filled radiator weighs 12 to 15 kg. A 1500W convection panel weighs 3 to 4 kg. Shipping from China to a US warehouse, the difference is roughly $4 to $6 per unit in ocean freight alone. On a 40-foot container holding about 500 oil filled radiators or 1,200 convection panels, that's a big margin hit.

If you're selling on Amazon, weight also affects FBA fees. A 15 kg oil filled radiator will cost you significantly more per unit in fulfillment than a 4 kg panel. Your price point has to cover that. Most Amazon sellers I talk to end up with convection panels for this reason alone.

Safety and certification: the non-negotiable

Both types are safe if built right. But oil filled radiators have a sealed oil tank that must withstand pressure. A cheap unit with thin steel is a leak risk. You need a supplier who pressure-tests every unit. Convection heaters have exposed heating elements behind a grille, so they need good tip-over switches and overheat protection.

For bathroom use, you need IP24 rating on either. That means splash-proof from any direction. We make both types with IP24, but convection panels are easier to wall mount in a bathroom because they're light. An oil filled radiator on wheels in a wet room is a bad idea.

If you're sourcing for the UK or EU, make sure your supplier has CE and UKCA. For the UK, you also need ERP compliance on energy labeling. We've seen buyers get stuck at customs because the supplier didn't provide the ERP file. Ask for it in writing before you place an order.

MOQ and lead time: what to expect

At our factory, the standard MOQ for either type is 200 pieces. Lead time for convection panels is 15 to 25 days. Oil filled radiators take 25 to 45 days because the oil filling and pressure testing add steps. If you're launching a new private label brand, start with convection. Faster to market, cheaper to ship, and easier to iterate on design.

What to source: a blunt recommendation

If you're selling to homeowners who want steady overnight heat in a bedroom, source oil filled radiators. If you're selling to apartment dwellers, office managers, or anyone with a tight budget and a need for quick heat, source convection panels.

If you're selling on Amazon, convection is usually the safer bet. Lower weight, lower FBA fees, fewer returns due to shipping damage. Oil filled radiators get damaged in transit more often because of their weight and the oil seals.

One honest takeaway: don't try to be both. Pick one technology, build your brand around it, and become the supplier that buyers trust for that specific product. A distributor who carries both ends up competing against themselves. A specialist wins the reorder.