Well Pump Installer flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Submersible pump stage

One impeller and diffuser assembly in a submersible pump; adding stages increases total head at a given flow while raising required brake horsepower.

Check valve function

A one-way valve that holds the discharge water column when the pump stops, preventing backspin and backflow; a leak causes rapid cycling or loss of pressure.

Bladder pressure tank

A tank with a flexible bladder separating air precharge from water; it stores drawdown volume and maintains pressure between pump cut-in and cut-out settings.

Pitless adapter

A fitting that connects the well drop pipe to the building service line below frost depth and seals the casing, allowing the pump to be removed without excavation.

Jet pump venturi

A nozzle-and-venturi ejector that converts pressure energy into velocity to lift water; shallow systems use one pipe and deep systems use two pipes.

Torque arrestor

A rubber or mechanical device installed above a submersible pump to center the pump and limit motor twisting during startup, protecting the drop pipe and cable.

Well seal

A cap assembly that seals the top of the well casing around the drop pipe, wiring, and vent while supporting the pump piping and preventing surface contamination.

Total dynamic head

The sum of vertical lift, drawdown, discharge pressure head, and friction losses in feet; used to select a pump that meets design flow.

Pressure head conversion

One psi equals 2.31 feet of water head; multiply pressure in psi by 2.31 to convert to feet, or divide feet by 2.31 to obtain psi.

Pump operating point

The intersection of the pump performance curve and the system head curve; it defines the actual flow, head, and power draw at a given installation.

Pressure tank drawdown

The usable water volume expelled as tank pressure falls from cut-out to cut-in; it determines pump cycle volume and run time.

Hydraulic horsepower formula

Water horsepower equals flow in gallons per minute multiplied by total dynamic head in feet, divided by 3960; brake horsepower equals water horsepower divided by pump efficiency.

Well yield

The sustainable flow a well can produce without excessive drawdown; pump capacity should not exceed yield unless storage or controls limit pumping.

Friction loss

Pressure loss caused by water moving through pipe, fittings, and valves; it rises with flow and pipe roughness and must be added to system head.

Two-wire submersible motor

A submersible motor with starting components built into the motor housing; it connects directly to the pressure switch and requires no separate control box.

Three-wire submersible motor

A submersible motor that uses an external control box containing the capacitor and relay; three motor leads plus ground run from the well.

Motor start capacitor

A capacitor in a single-phase motor control box that provides starting torque; a failed capacitor can cause humming, tripped overloads, or failure to start.

Pressure switch cut-out

The upper pressure setting at which the switch opens and stops the pump; it must match tank precharge and system design pressure.

Voltage drop limit

Recommended maximum voltage drop is three percent on a branch circuit and five percent overall; excessive drop causes motor overheating and reduced starting torque.

Insulation resistance test

A test using a megohmmeter to measure motor and cable insulation resistance to ground; low readings indicate moisture damage or failing insulation.

Pump setting depth

Depth chosen so the pump intake stays below expected drawdown and above the well bottom, while allowing motor cooling flow and avoiding sediment.

Pressure tank precharge

Air pressure in a bladder tank with the water side drained; typically set two psi below cut-in pressure for a 20 psi pressure differential.

Well disinfection

Treatment of the well and piping with a chlorine solution after installation or repair, followed by flushing, to reduce bacterial contamination risk.

Startup amp check

Measurement of running current on each motor lead at design flow; current should match nameplate or pump curve and be balanced within acceptable limits.

Constant-rate flow test

A test that pumps at a fixed rate while recording water level and time to estimate sustainable yield and allowable drawdown for pump sizing.

Submersible wire splice

A waterproof, heat-shrink or resin-filled connection that restores insulation and strain relief on submersible cable; poor splices cause ground faults.

Short cycling

Rapid pump starts and stops caused by a waterlogged tank, leaking check valve, faulty pressure switch, or oversized pump relative to storage.

Loss of prime

A condition where a jet or suction pump has air in the suction line and cannot build pressure; causes include low water, leaks, or a failed foot valve.

Lockout tagout

An energy-control procedure that isolates electrical or mechanical power, applies a lock and tag, and verifies de-energization before service work.

Backflow prevention

Devices or air gaps that prevent contaminated water from reversing into a potable supply; required where cross-connections or chemical injection exist.

Confined space entry

Entry into a well pit or vault with limited egress and possible hazardous atmosphere; requires testing, ventilation, attendant, and rescue provisions before entry.

Sanitary well cap

A vermin-proof cap that seals the casing, vents the well, and excludes surface water and insects; a damaged cap allows contamination.