Oil Filled Radiator vs Convection Heater: What to Source

You're a buyer, not a physicist. You need to know which heater type to put in your container, and you need to know it without a sales pitch. Let's cut through the noise on oil filled radiator vs convection heater, because these two are the most common SKUs we ship, and they serve different masters.

I've been building these units since 2009. I've seen buyers lose money by guessing wrong. Here's the real difference, and how to choose based on your market, not on what looks sleek in a catalog.

The Core Difference: Heat Transfer, Not Heat Generation

Both units use the same electric heating element. The difference is how they release that heat.

An oil filled radiator heats thermal oil inside a sealed metal column. The oil holds heat long after the element cycles off. It radiates heat from the metal surface, and it creates a gentle convection current as air passes over the fins. It's slow to warm up, but it keeps warming after the thermostat clicks.

A convection heater (wall-mounted panel or portable) uses a bare element or a finned tube to heat air directly. Air passes over the element, rises, and pulls cooler air from the floor. The room warms faster, but the heat stops almost instantly when the unit turns off. No thermal mass, no stored heat.

That's the whole game. One stores heat, one doesn't.

Where Oil Filled Radiators Win

Oil filled radiators are the right call for bedrooms and living rooms where people sit still for hours. They don't blow air, so they don't stir up dust or dry out your eyes as much. They're also silent electric heater options, which is a phrase we see in buyer emails constantly. No fan, no click, just the occasional tick of the thermostat.

They're also better for continuous heating. If a customer wants to run a heater for eight hours overnight, an oil filled radiator will cycle on and off less frequently because the oil retains heat. That means fewer cold drafts and a more stable room temperature.

From a sourcing standpoint, oil filled radiators are heavier. A 2000W model with seven fins weighs around 15-18 kg. That eats into freight costs, but it also feels substantial to the end user. Customers equate weight with quality, and they're not wrong in this case.

Where Convection Heaters Win

Convection panels are the answer for quick heat and for spaces where you don't want a heavy metal box on the floor. Wall mounted electric heater models are almost all convection type. They're slim, they mount flush against a wall, and they're ideal for offices, workshops, and garages where floor space is precious.

They're also cheaper to ship. A 1500W wall panel weighs about 4-5 kg. You can fit three times more units in the same container. If you're doing Amazon FBA, that weight difference is a dealbreaker. Your landed cost per unit is significantly lower.

Convection heaters are also better for intermittent use. If someone is in a garage for an hour and wants it warm fast, a convection unit delivers. Oil filled will still be warming up when they're ready to leave.

The Real Comparison: Running Costs and Efficiency

Here's where buyers get confused. Both types are 100% efficient at converting electricity to heat. That's physics. The difference is in how they feel, not in the wattage consumed.

An energy efficient electric heater is a marketing term, not a technical spec. A 1500W oil filled radiator and a 1500W convection panel use the same electricity per hour. The difference is that the oil filled unit may cycle off sooner because it stores heat, so it might use less energy over a full night. But that depends on the room insulation and the thermostat setting.

If your customers ask about electric heater running cost, give them the math. At $0.15 per kWh, a 1500W unit costs $0.225 per hour. That's the same for both types. The only way to save is with a thermostat that cycles the unit off, and with proper sizing.

Sizing and Placement

For a large room, you need roughly 10 watts per square foot. A 1500W unit covers about 150 sq ft. A 2000W unit covers 200 sq ft. Don't oversell a 1500W unit for a 300 sq ft garage. It won't work, and you'll get returns.

Oil filled radiators work best in enclosed rooms with doors closed. They don't do well in drafty spaces because they rely on slow convection. Convection panels work better in rooms with some air movement, but they also struggle in very drafty spaces. If your customer is asking about a garage or workshop, they need a fan-forced heater instead. That's a different product line.

Certifications and Compliance

Both types need CE and RoHS for Europe. For the UK, you need UKCA. For energy labeling, you need ERP compliance. We do all of these in-house. If a supplier doesn't have these certs, walk away.

One thing to check: oil filled radiators have a higher risk of oil leaks in transit if the seams aren't welded properly. We've seen cheap units arrive with oil residue on the carton. That's a return nightmare. Ask your supplier about their leak test process. We pressure test every unit before packing.

Our Manufacturing Reality

Standard MOQ for both types is 200 pcs per model. Lead time is 30-45 days for a mixed container, 15-20 days for a single model. We can do custom colors, custom wattages, and private label branding. If you want a wifi smart electric heater, we can add that module, but it adds cost and requires app certification.

For Amazon sellers, we recommend convection panels for the weight advantage. For retail distributors selling to homeowners who want quiet overnight heat, oil filled radiators are the better bet. For private label brands, both work, but you need to know your target customer's room size and heating habits.

The Honest Takeaway

Don't ask which type is "better." Ask which type fits your customer's room, budget, and shipping reality. Oil filled radiators win on comfort and silent operation. Convection panels win on cost, weight, and speed. Sell the right one for the right room, and you'll get fewer returns and more reorders. That's the whole job.

If you're still unsure, order samples of both. Run them in the same room, same settings, for a week. You'll feel the difference in your bones. Then you'll know what to put in your next container.