Central heating radiators come down to three checks: output, size and how the unit sits on the wall. More panels or convector surface usually give you more heat from the same footprint, while single-panel options suit tighter spaces and lighter loads. If the pipework and wall space are fixed, dimensions matter as much as output - the wrong size is the one that causes the call-back.
Halcyon TPL Convector Radiator Type 33/K3 - 600mm x 600mm
600mm x 600mm Type 33/K3 convector radiator for home and commercial use
Myson Premier Round Top Double Convector Radiator
Round top double convector radiator, high output
Stelrad Prorad Type 11 Single Panel Single Convector Radiator - 400mm x 600mm 40…
Type 11 compact radiator 400 x 600 millimetres, 406W output
Stelrad Halcyon Compact K1 Single Panel Radiator - 600mm x 800mm
600mm x 800mm white gloss Type 11 radiator, 774W
K-Rad Kompact Radiator Type 21 - 500X1400MM
Type 21 radiator, 500 x 1400mm, white powder-coated, 10-year guarantee
Stelrad Softline Compact Type K1 Steel Panel Radiator 2676BTU - 600 x 800mm
600 x 800mm steel panel radiator, 2676 BTU, Traffic White compact design
Type 22 Double Radiator - 500 x 900mm 4807 BTU
Type 22 double panel convector radiator, 500 x 900mm, 4807 BTU, white enamel fin…
Stelrad Elite P+ Radiator - 450 x 600mm (18 SEC)
Stelrad Elite P+ Type 21 radiator 450x600mm, two-coat paint finish
Prorad Radiator Double Panel No21 - 500mm x 900mm 3608 BTU
Compact double panel radiator 500x900mm, 879W output, 10-year warranty
Revive Radiators Revive2 Double Panel Double Convector K2 Compact Radiator - 400…
K2 compact radiator, 400 x 400mm, 1719 Btu, 10-year guarantee
For central heating radiators, start with the system and the job spec, not the finish. A standard wet system usually keeps you in the same family of product, but the real checks are output, depth, and whether the pipework and wall space will take the size you want. On a tight swap, a slimmer panel can be easier to land. If the room needs more heat, you may need a deeper unit or a larger footprint. The install package matters too. Flue route, filter requirement, fuel type, and who’s signing it off all change what you should be buying.
Flat panel central heating radiators are the usual pick when you want a straightforward swap and do not need much depth off the wall.
If you need more output from the same footprint, a double panel or double convector version gives you that. The trade-off is depth. It sits further out and can be tighter on pipe centres and clearance.
Single panel units are slimmer and easier to place where space is awkward, but you give up output. Once you have fixed the room layout, Radiators is where you step back and compare the wider range against the job.
The first check is output against space. A deeper unit gives you more capacity, but it also stands further off the wall and takes more room around pipework, skirting and furniture.
On a straight swap, that often matters more than the finish. For tighter spaces or lighter loads, a slimmer panel is usually the cleaner fit. Column Radiators suit jobs where the look is part of the brief and you can live with the extra depth. Designer Radiators come in when appearance is driving the choice, but you usually give up some simplicity and sometimes some output for that.
Once you’ve picked the unit, the next call is what sits around it. If the room needs a cleaner finish, radiator covers are the usual add-on, but they do reduce output a bit and make access tighter when you’re back for a valve change.
Radiator foil is worth considering on older external walls where you want heat back into the room rather than into the masonry. For a neater install, radiator valves and the right parts and accessories matter more than people think - it’s usually the small mismatches that slow you down on site.







