Charges with gas main from the east must incorporate value (7)
I believe the answer is:
aerates
'charges with gas' is the definition.
(I've seen this in another clue)
'from the east must incorporate value' is the wordplay.
'from the east' says the letters should be written in reverse (on a map from right to left).
'must' becomes 'sea' (I am not sure about this - if you are sure you should believe this answer much more).
'incorporate' means one lot of letters goes inside another.
'value' becomes 'rate' (both can mean to esteem).
'sea' backwards is 'aes'.
'aes' placed around 'rate' is 'AERATES'.
'main' acts as a link.
This may not be correct. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for aerates that I've seen before include "Brings gas" , "Puts fizz into a drink" , "uses fork to do it?" , "fans" , "Pumps carbon dioxide into" .)