On Jul 20, 6:50 am, "Edwin Pawlowski" wrote:
kjpro @ usenet.com wrote in message

...



Don't you think his water system has a check valve?

I don't know of many that do. Mine certainly does not. Not in my last
house either. Or the one before that. Why do you think he has one?

Backflow preventers are relatively new in residential applications also. I
have four in my commercial/industrial buildings, none in residential.

.Backflow preventers are relatively new in residential applications also.

Yes & in some areas, backflow prevention is handled only at hose bibs
& dishwashers via individual devices.

My neighbor had a city permitted / inspected re-pipe & now has vacuum
breakers at the hose bibs.............no check valve & thus no need
for an expansion tank.

cheers
Bob