Maybe you've never seen closed loop systems or are overlooking equivalent expansion valves because "California Plumbing Code (Section 608.3) and the California Mechanical Code (Section 1005.0) requires a thermal expansion tank, or listed equivalent, to be installed to water heating systems to relieve excessive building pressure during the heating process."
wrong ... the house water pressure when you install it will turn up the air pressure inside by pushing on the bladder then you adjust it on a filled cold water tankand air removed from piping . thus when the water heats up the bladder moves takeing up the over pressure
I live in CA and have never seen one of these installed.
Maybe you've never seen closed loop systems or are overlooking equivalent expansion valves because "California Plumbing Code (Section 608.3) and the California Mechanical Code (Section 1005.0) requires a thermal expansion tank, or listed equivalent, to be installed to water heating systems to relieve excessive building pressure during the heating process."
wrong ... the house water pressure when you install it will turn up the air pressure inside by pushing on the bladder then you adjust it on a filled cold water tankand air removed from piping . thus when the water heats up the bladder moves takeing up the over pressure