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Water Pressure-well

I just moved to the country. We are on a well. We were told by inspector that we have excellent water flow. The problem -- while showering, the water pressure ebbs and flows in waves. It also seems kinda "low pressure" to what I had in the city of Dayton, Ohio. There is a water softener and a 30 gallon hot water heater attached (which I plan to replace with a 50 gallon), also a 20 gallon pressure diaphram (that I have no idea what it does). What do I need to do to increase the pressure of the water in the home and also outside on the faucets?
Please help this city boy adjust to the country !!

Re: Water Pressure-well

If you have a pressure switch like the one pictured here You can remove the cover and there will be one or two adjusting screws to adjust the pressure(instructions should be on the inside of the cover). They come from the factory preset for 20/40 lbs or 30/50 lbs. The 20/40 set unit will turn on the pump when the pressure is less than 20 lbs and off when the pressure is greater than 40 lbs. Once you increase the pressure the pre-charge in the bladder tank should be adjust to about 2 lbs less than the on pressure. Personally I would not recommend adjusting the pressure to more than 40/60 lbs.


Re: Water Pressure-well

Good explanation above, but before you go and change things, the reason for the fluctuation in water pressure is to keep the pump from wearing out the pump prematurely. The pump runs long enough to build up pressure in the tank, then it shuts off until the pressure drops to the lower limit.

The 20 gallon "pressure diaphragm" is an accumulator. That is a tank that is half filled with water and half air. Water will not compress, air will. The air acts like a cushion. Since your tank is only 20 gallons, it takes three to four gallons of water to go between the high and low limits. That means the pump gets the tank up to the high limit, say 40 psi, then the air pressure pushes water out to the shower until the pressure gets down to the lower limit, say 20 psi when the pump kicks back on.

Since you described your accumulator as a pressure diaphragm, it probably uses a rubber diaphragm to keep the air from being absorbed into the water. Tanks without a diaphragm can get "waterlogged" causing the pump to constantly cycle on and off and causing damage to them. Those without a diaphragm usually have an "air injector" to keep this from happening.

Before you change the pressure switch to one with values that are closer together, like a 60/40, be sure the pump is designed for the increased pressure.

Welcome to life on the well. You'll get used to it.

Re: Water Pressure-well

It sounds like the bladder is gone in the tank. If you get water out of the snifter valve on the top of the tank it's gone. The only fix for that is to replace the tank.


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