According to the techs at the company we had install a new furnace, residential fixtures are only rated to 85 psi. They recommend a max of 65 psi.
The pressure in the town we live in is about 140 psi and folks use a pressure reducer. The Watts adjustable is the one most use.
The one on our house had failed sometime before we bought it a couple of years ago and I didn't discover it until a friend hooked his coach up to our water and his hose swelled up a lot.
Even though our fixtures and copper plumbing held up okay at 140 psi I would still be leery of 85 psi and would install a regulator.
