Some heat from another machine (5)
I believe the answer is:
therm
'some heat' is the definition.
(Therm is a unit of heat energy)
'from another machine' is the wordplay.
'from' indicates a hidden word.
'THERM' is hidden in the letters of 'another machine'.
(Other definitions for therm that I've seen before include "Unit of measurement of heat" , "Unit of heat as in gas supply" , "Former gas supply unit" , "Unit of heat and gas measure" , "Unit of heat energy" .)