Single, double or triple: understanding panel types
The biggest decision with a panel radiator is how many panels and convector fins it has. Brands name these in two ways, so the same build can appear under different labels.
Single panel, single convector (Type 11 or K1)
One panel with one set of fins.
Double panel, single convector (Type 21 or P+)
Two panels with one set of fins between them. More heat than a single at the same height and width.
Double panel, double convector (Type 22 or K2)
Two panels with two sets of fins, often what people mean when they search for a "double radiator". More heat again at the same size.
Triple panel (Type 33 or K3)
Three panels with three sets of fins, for more heat again at the same size. Listed in ranges such as Myson Select Compact and Stelrad Vita Compact.
Double panel, no convector (Type 20 or P2)
Two panels with no fins. Type 20 is P2, not P+. Some ranges, such as Stelrad Compact With Style, list a "Double P2".
Our radiator terms explained page explains the names.
Sizing a panel radiator
Measure first
Panel sizes are written height × width in millimetres, for example 450 × 1600 mm. Many searches use the opposite order, so check which figure is the height.
Then match the output
Get an estimate of the room's needs from our BTU calculator, which gives a figure in BTU, then pick a size and type whose listed output meets it. Each product page shows its rated output, and the test condition (ΔT) where it is stated. Outputs are only directly comparable when both products state the same ΔT.
Horizontal and vertical
Most panels are horizontal. Vertical panels, such as the CenterRad Streyt, use wall height rather than wall width.
Finishes and power source
White and RAL 9016 traffic white are standard, with anthracite on some ranges. Most panels connect to a wet central heating system; electric models are also in the Electric Radiators collection.
Popular panel ranges
Start with Stelrad Softline, Myson Premier HE Metric or CenterRad Compact, or use the radiator finder to search every brand from your measurements.