new tank / pressure switch acting up

I had a new pressure tank installed today. When the plumber left, I noticed the cut on / off pressure is around 35/45. Also, when it gets to 35, the pressure drops quickly to about 30, creating a lag in water pressure before the pump kicks on. I just checked and the factory precharge is 38 psi. Do you think the problem is that the plumber set the gauge on/off pressure too low? From what I've read, it sounds like it should be set at 40/60.

pressure problem

The air pressure in the pressure tank should be 2 pounds less than the cut in pressure of the pump . The air pressure in the pressure tank must be checked with the pressure tank drained of water . Your statement that the cut on / off pressure is 35/45 is a little confusing . There should be 20 pounds difference between cut in & cut off . You are correct that with 38 pounds air pressure in tank the pump should cut on at 40 & off at 60 . Sounds like your pressure switch needs adjusted .

You should demand that the Plumber come back and do it right this time. The information WV Hillbilly gave you can be passed on to the Plumber so he can set your pressure where it should be. This may be a bit embarrassing to him, and that's ok.

bob...