Vertical pressure tank connected to a water pump outdoors

Well system pressure slowly getting weaker

A slow decline is most often a filter or treatment unit clogging up between the tank and the house. Next suspects are the pressure switch settings or a clogged switch port, the tank air charge, and finally a worn pump or falling water level.

Cross-checked ~45 min moderateBrands: All

Before you start

Turn off the pump breaker before adjusting the pressure switch or checking the tank air charge.

Diagnostic steps

Unlock all 4 steps with expected values

Full library + AI assistant for $34.90, one time.

Get lifetime access

OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

More sump & well pumps guides

Guide · Sump / Well Pump

Sump pump trips the GFCI or breaker

A GFCI that trips with a sump pump is usually detecting real current leakage from a pump motor taking on water, a damaged cord or splice, or another load on the same circuit. Isolate the pump from the circuit before blaming the GFCI, and never bypass the protection on a pump in water.

4 steps ~45 minmoderate

Guide · Sump / Well Pump

Sewer or musty smell from the sump pit

A clean sump pit should not smell like sewage. Most odors come from a pit that has dried out and no longer seals the drain tile lines, stagnant water, organic buildup, or nearby plumbing traps that have dried or been siphoned. A strong, persistent sewage smell can mean a leaking sewer line near the pit.

6 steps ~30 mineasy

Guide · Sump / Well Pump

Sump pump keeps cycling when it has not rained

The most common cause is water returning from the discharge pipe through a failed or missing check valve, so the pump moves the same water again and again. Other causes are a small basin, a float set too close, a high water table or a leak feeding the pit.

4 steps ~40 mineasy