Type 22 Radiators (Double Panel/Double Convector)

A Type 22 radiator has two panels and two convector fins, which makes it the highest-output compact radiator for a given wall size. If you need serious heat from a limited run of wall, this is the specification to choose.

Type 11, 21 or 22?

• Type 11 — single panel, single convector. The slimmest at around 50mm deep, and the right choice where projection into the room matters more than output.
• Type 21 — double panel, single convector. A middle ground at roughly 70mm deep.
• Type 22 — double panel, double convector. Around 100mm deep, and typically double the output of a Type 11 of the same dimensions.

Sizing it properly

Work out the room's heat requirement in BTUs before choosing, rather than matching whatever was there before. An undersized radiator will never warm the room however long it runs; an oversized one wastes money and floor-to-wall space. Output figures assume a 50°C temperature difference — if your system runs cooler, as heat pump systems do, the real output will be lower.

Fitting

Type 22 units are heavy, especially in longer widths. Make sure the wall and brackets can take the weight when full of water, and allow clearance at the bottom for the valves.