See unit refurbished as part of a set (2,5)
I believe the answer is:
en suite
'as part of a set' is the definition.
(as in en suite rooms)
'see unit refurbished' is the wordplay.
'refurbished' indicates anagramming the letters.
'see'+'unit'='seeunit'
'seeunit' with letters rearranged gives 'EN SUITE'.
(Other definitions for en suite that I've seen before include "Attached as part of a unit, bathroom say" , "Together by bedroom" , "Forming a unit or set" , "(Of bathroom) immediately adjoining bedroom" , "(Of bathroom) accessible from the bedroom" .)