Originally Posted by
Gunnar Alquist
The one problem that I have with the diagram that you posted is that the hot water is not clearly bonded.
Depends.
If not dielectric unions are installed, then the hot and cold are bonded through the water heater. This can be done with brass fittings when using copper piping. When using galvanized piping in older homes, that also did the trick.
Both hot & cold are required to be bonded. At least, around here they are.
When dielectric unions are installed, yes, that would be needed. Many dielectric fittings maintain mechanical and electrical contract while lining the interior of the fitting with plastic to isolate the fitting from the water, those also maintain bonding contact.
It is quite probable that, to ensure that future repairs do not 'break the bond', that the hot piping needs to be bonded to the cold piping. Makes sense and is a 'good thing to do', but "required"? Not knocking it, anything which improves it is good with me, just pointing out the other side of why many areas do not "require" it.