Home Well Pump Performance Key Maintenance Tips

Imagine waking up to a dry faucet – no water for your morning coffee or shower. Residential well pumps are the unsung heroes of household water systems, and their electrical resistance ("ohm") values hold the key to reliable operation. Here's what every homeowner should know about maintaining these critical systems.

Submersible pumps operate underwater, pushing water vertically to the surface. These units excel in deep wells due to their efficient design and lower maintenance requirements. The submerged placement allows for better heat dissipation, extending service life. When selecting a submersible pump, consider well depth, water demand, and power capacity to ensure consistent performance.

Installed above ground, jet pumps create suction to draw water from shallow wells (typically under 25 feet). While less efficient than submersibles, they offer cost-effective installation and maintenance. Dual-jet models provide enhanced lifting capacity for marginally deeper applications.

Electrical resistance measurements serve as a diagnostic tool for pump health. Proper ohm values indicate intact motor windings, while abnormal readings may reveal:

• Shorted windings (low resistance)
• Open circuits (infinite resistance)
• Ground faults (abnormally high resistance)

This critical housing contains relays, capacitors, and protective devices that manage power delivery. Understanding wiring diagrams helps troubleshoot issues that often originate here.

Start and run capacitors provide the extra torque needed during motor activation. Failed capacitors often manifest as:

• Swollen or leaking housings
• Difficulty starting
• Complete startup failure

This automatic switch activates the pump when pressure drops below preset levels (typically 30-50 PSI) and shuts it off when reaching upper limits. Malfunctions cause:

• Erratic water pressure
• Continuous pump operation
• Failure to activate

Using a multimeter set to ohms:

1. Disconnect all power sources
2. Connect leads between ground and power terminals
3. Select appropriate range (typically 0-20 ohms for motors)
4. Record stable readings (avoid "OL" over-range indications)

Healthy motors typically show:

• 5-20 ohms between windings
• 500k-2M ohms to ground

A megohmmeter checks for complete current paths. Low resistance confirms proper connections, while infinite resistance reveals breaks in the circuit.

10,000-20,000 ohm readings often indicate:

• Moisture intrusion
• Winding deterioration
• Failing insulation

Frequent tripping suggests:

• Overcurrent conditions
• Short circuits
• Ground faults (check for water in wiring)

• Monthly: Inspect wiring, check pressure tank, listen for unusual noises
• Annually: Professional inspection, capacitor testing, resistance checks

1. De-energize at the breaker
2. Secure lifting equipment
3. Inspect components (bearings, impellers, wiring)
4. Clean and reinstall carefully

• Always verify power disconnection with a voltmeter
• Use insulated tools
• Repair damaged insulation immediately

Ensure proper amperage ratings match pump requirements. Undersized breakers nuisance trip, while oversized units fail to protect.

Typically 10-50 ohms between windings, with 500k+ ohms to ground.

After powering down, inspect connections, test relay continuity, and verify capacitor function.

15-40 ohm readings between windings suggest proper operation.