Type 22 or type 33 radiator: which one to choose?
In short
- A type 22 has two panels and two rows of convector fins, a type 33 three of each. At the same size, a type 33 gives 37 to 39% more heat on our Belrad radiators: at 600 x 1000 mm, 2,389 W against 1,732 W.
- In return, a type 33 is thicker (158 mm against 100 mm according to Stelrad), 50% heavier and 41 to 44% more expensive at the same size.
- A type 33 helps when wall length is short: 2,389 W on 1 m, where a type 22 needs 1.40 m for 2,425 W. Otherwise, the type 22 remains the cheaper choice.
Choosing between a type 22 and a type 33 panel radiator comes down to the heat output the room needs and the space on the wall. A type 33 gives more heat from the same surface, a type 22 is slimmer, lighter and cheaper. This guide compares both on the Belrad radiators in our range, with their real outputs and prices.
Last updated: October 2026. Prices recorded in the shop on 06/10/2026, VAT included.
What do type 22 and type 33 mean?
The type describes how a panel radiator is built. The first digit is the number of water panels, the second the number of convector fin rows behind them. A type 22 therefore has two panels and two fin rows, a type 33 three panels and three fin rows.
The more panels and fins, the larger the surface giving heat to the air, and the more the radiator heats at the same size.
How much more output at the same size?
At the same height and length, a type 33 gives 37 to 39% more heat than a type 22 on our 6-connection Belrad radiators. The outputs below are the manufacturer's figures under standard EN 442 (water at 75 °C flow, 65 °C return, room at 20 °C).
| Size (H x L) | Type 22 · price incl. VAT | Type 33 · price incl. VAT | Extra output |
|---|---|---|---|
| 400 x 1000 mm | 1,245 W · €109.48 | 1,711 W · €157.01 | +37% |
| 500 x 1000 mm | 1,494 W · €120.69 | 2,056 W · €173.56 | +38% |
| 600 x 1000 mm | 1,732 W · €130.84 | 2,389 W · €187.97 | +38% |
| 600 x 1200 mm | 2,078 W · €153.27 | 2,867 W · €220.01 | +38% |
| 600 x 1400 mm | 2,425 W · €175.69 | 3,345 W · €252.60 | +38% |
| 900 x 1000 mm | 2,395 W · €176.99 | 3,334 W · €249.61 | +39% |
The price gap follows the output gap: at the same size, a type 33 costs 41 to 44% more. The price per watt therefore stays close, with a slight edge for the type 22: at 600 x 1000 mm, 7.6 cents incl. VAT per watt against 7.9 for the type 33.
Type 33: more heat on less length
The real advantage of a type 33 is fitting high output on a short wall. For about 2,400 W, here are three options from our range:
| Type | Size (H x L) | Output | Price incl. VAT |
|---|---|---|---|
| Type 22 | 600 x 1400 mm | 2,425 W | €175.69 |
| Type 22 | 900 x 1000 mm | 2,395 W | €176.99 |
| Type 33 | 600 x 1000 mm | 2,389 W | €187.97 |
A 1 m type 33 replaces a 1.40 m type 22 for about €12 more. If the height under the window allows it, a 900 mm tall type 22 gives the same output on 1 m, at a type 22 price.
Depth, weight, water content: what changes?
A third panel makes the radiator thicker and heavier. Our 6-connection Belrad radiators state exactly the same outputs as the Stelrad Novello range, so we use Stelrad's technical documentation for 600 mm tall panel radiators:
| Per metre of length, 600 mm tall | Type 22 | Type 33 |
|---|---|---|
| Depth | 100 mm | 158 mm |
| Output (EN 442, 75/65/20 °C) | 1,732 W | 2,389 W |
| Weight | 35.0 kg | 52.5 kg |
| Water content | 6.6 l | 9.8 l |
The extra 58 mm of depth matters in a narrow hallway, behind a door or in a recess. So does the weight: a 600 x 1000 mm type 33 weighs about 53 kg empty and needs a wall that can carry it.
Type 22 or 33 with a heat pump?
With cooler water, every radiator delivers less than its stated output. In Stelrad's EN 442 table, a 300 x 1000 mm type 22 drops from 982 W at 75/65/20 °C to 499 W at 55/45/20 °C, about half. A type 33 of the same size drops from 1,349 W to 690 W.
A type 33 therefore does not heat better at low temperature, it simply keeps the same advantage of about 37%. That helps make up for the lost output without a longer radiator. With a heat pump, sizing is done at the installation's real flow temperature: have it checked by your installer.
How to choose between type 22 and type 33?
- The wall is long enough: choose a type 22. At the same output it is slimmer, lighter and slightly cheaper.
- The wall is short, or the space is under a window: a type 33 gives the required output on less length.
- Depth is limited (hallway, door, recess): a 100 mm type 22 fits better than a 158 mm type 33.
- You are replacing an existing radiator: note the type, height and length on its label and aim for the same output. If in doubt, work out what the room needs.
Frequently asked questions about type 22 and type 33 radiators
What is the difference between a type 22 and a type 33 radiator?
A type 22 has two panels and two fin rows, a type 33 three of each. At the same size, a type 33 gives about 37 to 39% more heat, but it is thicker (158 mm against 100 mm) and heavier.
Does a type 33 radiator use more energy than a type 22?
No. A central heating radiator uses nothing itself: it gives off the heat produced by the boiler or heat pump. What matters is how much heat the room needs, not the radiator type.
How deep is a type 33 radiator?
About 158 mm, against 100 mm for a type 22, according to Stelrad's technical documentation. Add the gap between radiator and wall.
Can a type 22 be replaced by a shorter type 33?
Yes, if the output is equivalent. A 600 x 1000 mm type 33 (2,389 W), for example, replaces a 600 x 1400 mm type 22 (2,425 W). Check the position of the water pipes, which will no longer line up.
How much does a type 22 or type 33 radiator cost?
In our 6-connection Belrad range, from €64.61 to €325.76 incl. VAT for a type 22 and from €127.27 to €351.92 for a type 33, depending on size.
See type 22 and type 33 radiators
The models mentioned are online with their size and output: see type 22 radiators or see type 33 radiators. Collection is at our shop in Schaerbeek.
Sources: Bati-Mat Shop range (prices incl. VAT recorded on 06/10/2026) · Stelrad, technical documentation “STR-TD-NL” (Novello and Novello 8 sheets, EN 442 heat output table) · Versa Group, “About us” (versagroup.be).