Ken Zoeller
If Bob is an individual doing his own work in his personnel residence, it is not illegal in most areas. It only become illegal if he where doing it for some one else for money. Bob is looking for help for his DYI project and you did not help him with your possibly wrong input. Bob I do not know the answer to your question. You might go to a DYI store and look for one of the many “plumbing books” up front and do a little research.
