Well Pump Amps, Watts & Breaker Size

Well Pump Power Requirements at a Glance#

A well pump is wired through a pressure switch, not a plug. A 240-volt submersible pump hangs down the casing and draws 8 to 13 amps for 1,920 to 3,120 watts behind a 20 to 30-amp breaker, while a 120-volt shallow-well jet pump pulls 8 to 12 amps and 960 to 1,440 watts on a 15 to 20-amp branch through a 5-15R outlet.

Well Pump Electrical Specifications#

A submersible well pump hangs far down the casing and switches on whenever the pressure tank drops, so its motor wires straight through a pressure switch rather than any plug a homeowner could reach. The deeper the well and the higher the horsepower, the larger the conductor that has to carry current all the way down to the motor.

Circuit and Breaker Sizing for the Well Pump#

The submersible pump's 8 to 13-amp draw sounds light, but the conductor has to carry that current the full depth of the well to the motor, so a deep, higher-horsepower pump takes a heavier gauge than the amps alone suggest. On the surface it lands on a 20 to 30-amp two-pole breaker at the pressure switch. The shallow-well jet pump sits above ground on a 15 to 20-amp branch, its motor within easy reach rather than at the bottom of the casing.

Dedicated Circuit and Disconnect for the Well Pump#

Because a home's entire water supply depends on it, a well pump always occupies a branch of its own, wired through a pressure switch that starts the motor whenever the pressure tank drops. A disconnect at the switch lets power be cut before anyone services the pump or the wiring. The breaker is sized from the pump's stamped rating and the run length rather than a spot amp reading, since the motor draws a heavy surge each time it starts against the head of water in the casing.

Installation and Safety Notes for Well Pump Wiring#

A submersible pump is wired directly through the pressure switch and a control box, so there is no receptacle — the work is landing the right gauge for the depth and connecting the switch. A shallow-well jet pump can match a cord to a 5-15R outlet where the maker allows. Sizing a conductor to carry current down a deep casing and wiring the pressure switch is a licensed electrician's and well contractor's job, and any new circuit is permit-and-inspection work.

Well Pump Electrical FAQ#

What breaker does a submersible well pump use?#

A 240-volt submersible pump sits on a 20 to 30-amp two-pole breaker at the pressure switch, sized to its draw and the depth of the well.

Is a deep-well pump hardwired or plugged in?#

A deep-well submersible pump is wired directly through a pressure switch and control box. Only a surface-mounted shallow-well jet pump might plug into an outlet.

When does a well pump run on 240 volts instead of 120?#

Deeper wells and higher-horsepower submersible pumps run on 240 volts to move the current efficiently down the casing. A small shallow-well jet pump can run on 120.

How does the pressure switch control the pump circuit?#

The pressure switch closes the pump's circuit whenever the pressure tank falls below its setpoint and opens it once the tank is recharged, cycling the motor automatically.

What conductor size feeds a pump at the bottom of the well?#

It is sized larger than the 8 to 13-amp draw alone implies, because the wire has to carry current the full depth of the casing to the motor without excessive voltage drop.

Can a shallow-well jet pump run on an ordinary outlet?#

A 120-volt shallow-well jet pump can plug into a 5-15R outlet where the manufacturer permits, since its motor sits above ground within reach.