Direction to shut off when temperature's dropped (5)
I believe the answer is:
south
'direction' is the definition.
(compass direction)
'shut off when temperature's dropped' is the wordplay.
I cannot quite understand how this works, but
'off' could be 'out' (both can mean wrong or inaccurate) and 'out' is found in the answer.
The remaining letters 'sh' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'to' is the link.
Can you help me to learn more?
(Other definitions for south that I've seen before include "1949 musical by Rodgers and Hammerstein, made into a film in 1958" , "Cardinal point" , "Direction to the right of sunrise" , "Antarctica" , "Compass point" .)