Chimney in pub by church produces effect (9)
I believe the answer is:
influence
'effect' is the definition.
(I know that influence is a type of effect)
'chimney in pub by church' is the wordplay.
'chimney' becomes 'flue' (I've seen this before).
'in' is an insertion indicator.
'pub' becomes 'inn' (an inn is a type of pub).
'by' says to put letters next to each other.
'church' becomes 'CE' (abbreviation for Church of England).
'flue' put within 'inn' is 'influen'.
'influen'+'ce'='INFLUENCE'
'produces' is the link.
(Other definitions for influence that I've seen before include "Sway, dominance" , "The prestige and power to affect others" , "Agency" , "good offices" , "Pull, clout" .)