ijcoffin
It may be that the air in the pressure tank has leaked out. If that is the case there is nothing to hold the pressure (water cannot be compressed. It is only the air in the tank that gets compressed.) What to do? Turn off the pump, disconnect the pipe that goes into the tank. Let all the water drain from the tank, (you may have to open a sink tap to allow air into the tank so the water can drain). Close the tap, reconnect the pipes and start the pump. There should now be sufficient air in the tank to maintain the pressure for a longer period of time. Good luck.

ticketoride04
well purple, not really sure what the problem is, however when I have the pump people out to all my rentals,it seems as though I ask the same questions. The answer is always the same...I either have a leak in the pipes below, there is a faulty gage that has rusted out and needs changing or the blatter is damaged or needs recharging with air or something similar. I changed out my pipes that had rusted once to pex tubing and no more problems. another time on another pump it was the gage on the tank that froze and had to be changed out. prior to that, the previous owner had just changed out the storage/pressure tank as the blatter had gone bad on him. Now I've gone 6 yrs without a problem in all the tanks and can't say anything other than call in a pro. Mine usually cost about 75 to have it diagnosed and the problem costs can very. Be careful, you want to remedy this at the surface now, rather then have someone have to pull your pump from 200' below and replace the pump...that's about 2500-3000 bucks

bobo
The air pressure tank needs to be recharged or the bladder in the tank is leaking.

coz
There could be crud in the pipe that goes to your pressure switch.or the switch could be bad. they are cheap. bo bo is correct the tank has a rubber diaphram in the middle of it. you can knock on the tank the top should produce a higher pitched sound(hollow) if not it is waterlogged(bad) it needs replacing. there is a valve on the tank same as a tire nsee if you get air out of it.If you get water tank is bad.