ph level in steam and h20 boilers

bo ramsour

hi

 in Dan's we got steam book he talks about the ph level in boilers i have never ever tested the ph level in a boiler so i bought some test strips and tested my residential boiler . and it was 6.8  which i think is alkaline

 what should the actual ph level be in a steam or  h2o residential  system?

 also Dan talks about adding vineger on page 46 of his  book

 . but how much vineger do u add? i by  the btu rating of the boiler? of the gallonage of the system

  thank you  bo ramsour , lakewood , colo