Incinerator’s features to include receptacle for ashes (7)
I believe the answer is:
furnace
'incinerator's' is the definition.
(I've seen this before)
'features to include receptacle for ashes' is the wordplay.
'features' becomes 'face'.
'to include' indicates putting letters inside.
'receptacle for ashes' becomes 'urn' (I've seen this before).
'face' placed around 'urn' is 'FURNACE'.
(Other definitions for furnace that I've seen before include "Chamber greatly heated" , "Incinerator" , "High-temperature oven" , "Chamber for heating minerals or metals" , "Extremely hot chamber" .)