Radiators

Do not install the apparatus near any heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat.

The radiators are broken.

The radiators were barely warm; that's why the flat was cold.

The radiators were hardly warm, which is why it was cold in the flat.

Mr. Walker made good money building automobile radiators—enough that he can now afford to collect, recondition, display in that shed—and light upon request—hundreds of nostalgic neon signs.