Well pump not working? Check these five things, in this order

A private well is four parts in a chain: power from your electrical panel, a pressure switch that decides when the pump runs, a pressure tank that stores water under pressure, and the pump itself, hanging in the well. When the taps go dry, any one of them can be the break. The pump is the most expensive and the least likely, and it is also the only one you cannot see.

So work up the chain from the cheap end. The first two checks need nothing but a flashlight and five minutes, and they solve a surprising share of no-water calls in Marion County, especially after a storm.

First: is it the whole house?

Open a tap in the kitchen and one in a bathroom, and an outside hose bib if you have one. If only one fixture is dry or weak, the well is fine and the problem is that fixture: a clogged aerator, a shut-off valve under the sink, or a water heater issue if it is hot water only. A well problem is a whole-house problem.

If you have a whole-house filter or softener, check its bypass valve too. A filter cartridge packed solid with iron or sediment can starve the whole house of pressure while the well behind it is working perfectly.

1. The breaker

Most well pumps run on a dedicated 240-volt breaker, a double-width switch in your panel that is often labeled "well" or "pump". A storm, a surge or a brief overload can trip it. A tripped breaker sits in the middle position or visibly out of line with its neighbors.

Reset it once: push it fully off, then back on. If the pump starts and water comes back, note the date. One trip after a thunderstorm is common. Trips that recur are a message.

2. The pressure switch, and the lever on its side

The pressure switch is a small gray box, usually about the size of a fist, mounted on the pipe near your pressure tank. It turns the pump on when pressure falls to the cut-in setting and off when it reaches cut-out. Common settings are 30/50 and 40/60 psi.

Many switches, including the widely used type with a low-pressure cutoff, have a short metal lever on the side. If pressure falls close to zero, because the pump ran dry, a pipe leaked or the power was out for hours, the switch cuts the pump off and stays off until somebody resets it. This is the reset button people are searching for when they ask whether a well pump has one.

1. Make sure the breaker is on.
2. Lift the lever to the start position and hold it there. Do not open the switch cover; there is live 240-volt wiring inside.
3. Watch the pressure gauge. When it climbs past about 40 psi, let the lever go back to its normal position.
4. The pump should keep running on its own until it reaches cut-out, then stop.

If the gauge will not climb while you hold the lever, or the switch drops out again within a day, something upstream is wrong: the pump is not delivering, the water level has fallen to the pump, or there is a leak between the well and the house. That is the point to call somebody.

3. The pressure tank

If the pump runs but pressure is weak, fades after a minute, or the pump clicks on and off every few seconds, the tank is the prime suspect. A healthy tank holds a cushion of air above a rubber bladder. When the bladder fails, the tank fills with water, the cushion disappears, and the pump starts and stops constantly. That pattern is called short cycling, and it is what kills pumps.

Knock on the tank from top to bottom. A healthy tank sounds hollow near the top. A waterlogged one thuds solidly all the way up. The full test, with a tire gauge, is in the short cycling article, and what a new tank costs is in the pressure tank cost guide.

4. The control box, if you have one

Some submersible pumps are "three-wire" pumps, and they need a control box, usually a small gray or green metal box on the wall near the tank or the panel. It holds the start capacitor and relay that get the motor turning. Two-wire pumps have these parts built into the motor and have no box.

Control box parts fail, and lightning surges are hard on them. A pump that hums or trips the breaker at start, or a box that smells burnt, points here. This is a contractor repair, but a much cheaper one than a pump, and a good contractor tests it before quoting anything that involves a rig.

5. The pump itself

Only after those four does the pump become the likely answer. The symptoms that genuinely point down the well are a breaker that trips the instant the pump starts, a motor that draws current but delivers no water, and a gradual loss of pressure over weeks that no tank or switch adjustment fixes.

A contractor can confirm most of this from the surface. Resistance and insulation readings on the drop cable separate a dead motor from a damaged wire without pulling anything. Ask for those readings. In Marion County the median well is 105 feet deep, so pulling a pump is a rig job, and it should be the conclusion of a diagnosis rather than the start of one. Well depths: Florida Well Data, Marion County well records

The whole chain on one table

What is different about a Florida well

Two things push Marion County pumps off line more than the national guides admit. The first is lightning: Central Florida has long been called the lightning capital of the United States, and a submersible pump is a long copper cable into wet ground. How storms damage pumps and what an arrestor does. The second is iron. Iron and scale can clog the small pipe fitting under the pressure switch, so the switch misreads the pressure. Cleaning it is a small repair that looks, from the kitchen, exactly like a big one.

National Weather Service Melbourne, Lightning information

If you have been through all five and the taps are still dry, you have done the diagnosis a good contractor would start with, and you can tell them exactly what you found. The six questions to ask before you agree to a new pump are the next step.

Questions people ask