Low Water Pressure From Your Well? Causes and Fixes

Weak well water usually traces to one of four things. The pressure tank, the pressure switch setting, or a restriction between the well and the tap. The fourth is a well that cannot keep up with the house. Water that flows weak is a different problem from no water at all.

Work it in that order and you save money. Surface parts are quick to check, and they fail more often than the pump. The pump hangs hundreds of feet down the casing, so blame it last.

What causes low water pressure when you have well water?

A national well owner group separates two things people mix up. Flow is how fast a pot fills. Pressure is what you feel in the shower.

The group’s own list is short. It names a faulty pressure switch, a clogged filter, an obstruction in the line, and a leak in the piping. It also lists a water table that has dropped, so the pump cannot reach its design pressure. Water treatment equipment added without raising the switch setting belongs on it too.

Start at the gauge near the pressure tank. Watch the needle while a faucet runs, and note where the pump starts and stops. Those two numbers point at the part, and they are where well pump repair begins.

Why does my well water pressure drop and then come back?

That is the pressure tank working, or failing at it. The pump fills the tank to the cut-out pressure and shuts off. The house then draws from the tank until pressure falls to the cut-in, and the pump starts again.

A tank holds far less water than its size suggests. An extension service puts the usable share near 20 percent of capacity. A 42 gallon tank gives up about 8 gallons before the pump kicks on.

A short dip with quick recovery is normal. A long sag, or pressure that never climbs back, is not. If pressure falls to zero instead, what to check when a well gives no water covers that case.

Why does my water pressure drop when I use two faucets on my well?

A national well owner group notes that pressure often drops on upper floors. It drops again when several water using appliances run at once. Two showers and a washer can outrun the pump.

Extension work on low yielding wells calls this peak demand. Those peaks usually last 30 minutes to 2 hours. If the pump cannot refill the tank as fast as the house empties it, pressure sags. It comes back when the demand lets up.

Well yield sets that ceiling. A U.S. Geological Survey report cites a study of 1,069 wells in Spartanburg, Greenville and northern Pickens counties. Yields ran from 0 to 200 gallons per minute, with a median of 8. A median of 8 means half of those wells gave less.

Why is my well water pressure not reaching 30 psi?

Start with the settings. Clemson Extension lists 20/40, 30/50 and 40/60 psi as the common pairs. The low number is the cut-in, where the pump starts. The high number is the cut-out, where it stops.

If the gauge stalls under the cut-in while the pump runs, something is stopping it from building. A leak in the buried line, a clogged filter or a worn pump all do that. So does a water level below what the pump was sized for.

Clemson adds a simpler possibility: a pressure switch that sticks, often because ants got into the contacts. Age matters too. A national well owner group says most residential wells last 20 or more years, and the pump wears out first. National cost guides put a well pump near 15 years.

Can I turn up the pressure switch?

Sometimes, within limits. A national well owner group says switches leave the factory with a 20 psi differential. Rated ranges run up to 100 psi, with differentials of 10 to 40 psi. That rating is the ceiling.

Raising the settings changes two things. The tank precharge moves with it, because the air charge belongs 2 psi below the cut-in. The pump has to make the new cut-out, and not every pump can.

The cover sits over line voltage, and the same group says that adjustment belongs to a well contractor. Some switches carry a low pressure cut-off that stops the pump when pressure drops about 10 psi under the cut-in. We set cut-in and cut-out when we replace a pressure switch, and we set the tank air charge to match.

Is the pressure tank the problem?

Often, yes. The air cushion inside the tank holds pressure between pump runs. When the bladder fails, the water absorbs that air and the tank goes waterlogged. The pump then clicks on and off every few seconds.

Short cycling gets expensive. Most wear on a well pump happens when it stops and starts. A dead tank shortens the life of the pump under it. We replace a tank with a failed bladder rather than repair it, and what a replacement tank costs walks through the market ranges.

Is the well itself running low?

Sometimes the pump and the tank are both fine and the well is the limit. Upstate wells draw from cracks in bedrock, and the level drops through a dry summer. Pressure that faded over months, with no failed part to find, points this way.

State monitoring records show how thin some wells run. One York County well near Lake Wylie is logged at 700 feet deep. One Chester County well is 98 feet deep, with the water level logged between 85 and 90 feet down. That leaves under 13 feet of water in the hole.

A low yield well is not a pump fault, and a bigger pump will not fix it. SCDES lists the options when a well runs short. Lower the pump if water sits deeper, or deepen the hole where the rock allows. Where neither works, drilling a new well is the last item on that list, not the first.

When should you call?

Read the gauge and note what pressure does while a tap runs. Note whether the pump clicks rapidly, runs without stopping, or never starts.

We trace low pressure through the power, the pressure switch, the tank, then the pump. Switches and waterlogged tanks get replaced at the surface. When the pump is worn out, we pull the drop pipe and the wire. The new pump is sized to the well’s depth and yield, and that work is repairing a well pump system.

Call Core Well Drilling at (864) 768-5688 and tell us what the gauge reads. We look at the system and put a free estimate in writing.