Next to a radiator is not generally good for any plant because of the extremes of temperature. Palms need humidity so it would need very regular spraying and maybe a dish of water nearby to keep the atmosphere moist. They should also have a couple of hours of sun each day when they're growing. Could you position it a bit further away from the radiator?
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It doesn't really need direct sun, but it should be within the fan of light from a window--not off to one side--ideally not more than 2 meters from the window. In my college days in Flagstaff, AZ, we kept one actually on the radiator, which was under the window, but we kept it on a tray of pebbles half submerged in water, which kept both the plant and us more comfortable.