Ok - it'll add a slight acidification to the mash, which usually isn't a bad thing, but of course if you're getting it to strike temperature loads of the co2 will get driven off anyway. Sparge, again slightly acidic which is a good thing, I cold sparge now which would let it stay cabonically acidic, if you're heating.... pffffft (that's a scientific pffffffft). Boil - all the co2 will be driven off anyway.
Ideally it would be good to measure the pH during the mash but for the rest of if it's just fizz from co2 then you're fine.