Well Pressure Switch Slipping from Original Setting

Question

I have a ~600-foot well that provides water to my house. About a year ago, I adjusted the pressure switch to increase the water pressure in my home. It was set to 20/40 (Cut-in/Cut-out), which was horrible water pressure, but only one person lived in the house then. When I made the adjustments, I set it to 60/80 for a household of 5. We also have a small holding tank fed from the blue well pressure tank. There is a filter between them, so the pressure drops a bit, and the best I could get on that holding tank's gauge was ~65 PSI. See diagram 1 for setup and flow description.

My problem is that my switch seems to have adjusted to the 45/65, causing low-pressure issues throughout the house. This includes only running one appliance (dishwasher, washing machine, shower, toilet, etc.) at a time, or it takes forever to fill. My question is my pressure switch going bad because it adjusted itself back down to 45/65? (and possibly lower as time goes on?) If not the pressure switch, what other culprits could it be? Another question is, how could I set up a better flow/system if diagram 1 is a poor design?

Diagram 1: Well Water > Pressure Tank > 20 Micron Filter > Holding Tank (100 Gal.?) > Filter 5 Micron > Water Sofener > House Tap Water (Est. 45-55 PSI)

Side note: I understand that running at higher PSI may cause earlier failures, but I need to have a higher PSI cause I have a house full of girls. I also understand that each filter/softener lowers the PSI to the overall house.

Update: My best guess the Pressure Tank is a 36-gallon tank. (Small/Medium blue tank). My best guess on the holding tank size is an 80-gallon steel tank. We do not have any chemical injectors, just a water softener that is pretty old. (Looking to replace this in the future.) The pressure was probably set to 50/70, not 60/80. As 80 seems too high, the more I think of it. Piping is 1 1/2 inch to pressure tank tee then drops to 1 inch. It then is reduced to 3/4 inch going up to the filters. (I want to re-plumb all this to 1-inch pex to get the max flow through the filters and softener, then drop down the 3/4 and 1/2 for the house

Answer 1

If your well was set up properly to operate at 20/40 PSI and you changed it to 60/80 without also changing other things (such as a much larger, or additional, pressure tank) I'd fully expect it not to work properly. Even more so if you failed to adjust the air pressure in the tank when the system was empty, but even if you did, the storage of the pressure tank is much smaller at 60/80 than at 20/40, so you need a (much) larger tank to provide adequate storage volume to limit pump cycling. Most tank drawdown charts only go to 40/60 on the high end.

The "holding tank" has nothing to do with water delivery, it's commonly there to provide adequate contact time for chlorine injection or other chemical treatment (which you don't mention having), and is functionally a wide spot in the pipe.

Other than that part, there are a variety of possible issues, some of which "short-cycling" the pump with an under-sized pressure tank may have exacerbated by causing excessive pump wear - the pump may no longer perform as designed, or may have been marginal for that pressure setting to begin with - depending on drawdown and recharge rate in the well, it's possible to set the cut-out so high that the pump can't get there until the well refills after water has been used, so it will just sit there and spin without pumping enough to turn the switch off. That may cause it to overheat and perform even more poorly...You may also be overdrawing what your well can produce.

Side-note: in most cases "pressure problems" are really "poorly designed plumbing system flow problems" - excess pressure loss from undersized or poorly laid out pipes in the house. There's plenty of pressure until someone actually tries to use the water...

Additional note: if the pressure reading is not the same before and after the filter with no water flowing the gauges probably are not going to read the same for the same pressure. There should be no difference in the pressure before and after a filter until water is flowing. Filters have a strong effect on pressure under flow, but none on pressure with no flow. So one or both of the gauges are suspect.