Steve....you have a problem writing about DIY plumbing in MA. As we are given to believe...it is seriously ILLEGAL in MA for a homeowner to do ANY plumbing beyond possibly putting a new washer in a kitchen faucet. MA is different that most of the other 49 states in that regard!
Now, in my neck of the woods ( southern Calif., transplanted from MA some 40 years ago!) just yesterday, a gas leak behind a clothes dryer literally lifted the roof off the house. When the dust settles, we will probably find a DIY issue at the root of that one!