Best Submersible Well Pump for a House (2026)

Plumbing Picks is reader-supported. As an Amazon Associate, we earn from qualifying purchases at no extra cost to you.

Quick answer from a licensed plumber: If the water is deeper than about 25 feet, use a submersible. For a house, buy the Red Lion RL12G10-3W2V (1 HP, 3-wire, control box included): Red Lion lists 12 GPM at 100 feet and 50 psi. For a cabin with shallow water, the 2-wire RL12G05-2W2V skips the control box. Size the pump from the maker’s table at your pumping water level, not from horsepower.

Our pick for most deep wells: the Red Lion RL12G10-3W2V 1 HP 3-wire submersible pump. Check the Red Lion RL12G10-3W2V on Amazon

A 4-inch submersible pump sits in the well under the water and pushes it up, which is why it works where a jet pump cannot: when the water is deeper than about 25 feet. Red Lion says its RL series is for drilled wells 4 inches or larger, to depths of 250 feet. For shallower water see our shallow well pump picks; this page covers the deep well pump. We chose three Red Lion pumps because they are the ones with the maker documents we could read and Amazon listings that were in stock and sold by Amazon on the check date.

Submersible Well Pumps Compared

Figures come from Red Lion’s RL series spec sheet. Each linked pump was listed in stock on Amazon, sold and shipped by Amazon, when we checked on September 28, 2026. The 12 GPM and 22 GPM labels are Red Lion’s rated flows; the table shows what each pump lists at a given pumping level.

I send an occasional note when a new guide goes up — repairs worth doing yourself, and the parts that actually last. No spam, no course funnel; written by a licensed Georgia plumber.

2-Wire vs 3-Wire, and 115 V vs 230 V

A 2-wire pump has its starting switch inside the motor. It connects to the pressure switch with two conductors and a ground. A 3-wire pump adds a control box, which Franklin says holds the starting capacitors and relay. Franklin says the box and motor must match in horsepower and voltage, and that a motor run without its box, or with the wrong one, can fail and voids the warranty. Red Lion says to mount the box where it is protected from rain, snow, high heat and temperatures below 14 °F. In Red Lion’s line, the 1/2, 3/4 and 1 HP 3-wire pumps include the box; the 1.5 HP RL12G15-3W2V does not, so check before you order.

115 V is only offered here on the 1/2 HP RL12G05-2W1V, which draws 12 A. The same 1/2 HP at 230 V draws 6 A. Everything larger is 230 V only. Lower amps means smaller wire over the same distance, as the cable table below shows. If you have a choice, 230 V is the one to use.

How to Size a Submersible Pump

1. Find the pumping water level. Red Lion defines it, for a submersible, as the vertical distance from the water level while the pump is running to the point of use. It is deeper than the resting level. The well driller’s report has the numbers. Red Lion says to set the pump using the driller’s record, the static level and the drawdown at the pumping rate, and at least 5 feet off the well bottom.
2. Find the flow you need. Red Lion’s guide says the pump’s GPM should equal the number of fixtures, counting faucets, toilets and water-using appliances, and gives an eight-fixture house as needing 8 GPM.
3. Read the pump chart. Red Lion’s chart for 8 GPM lists the 1/2 HP RL12G05 at pumping levels of 50 to 100 feet, the 3/4 HP RL12G07 at 80 to 150 feet, and the 1 HP RL12G10 at 200 to 250 feet.
4. Check the performance table. Find your pressure (50 psi for a 30/50 switch) and your pumping level, and read the GPM. If it is below your need, go up a size. Red Lion lists 12 GPM for the RL12G10 at 50 psi with the pumping level at 100 feet, and 9 GPM at 200 feet.
5. Make sure the well can feed it. Red Lion says to run a well test with a partly open valve and check that the pump output is not greater than the well’s yield.

Wire Size From the Maker’s Table

Red Lion’s catalog gives maximum cable length in feet by copper wire size, for a 5% voltage drop and two- or three-wire cable. Franklin Electric’s manual gives the same numbers for the same motor ratings and adds larger sizes; for a 1 HP, 230 V motor it lists 990 feet on #8, 1,540 feet on #6 and 2,380 feet on #4. Franklin says the length is the total cable from the power supply to the motor, and to multiply by 0.6 to get the length for a 3% drop. It says aluminum must be two sizes larger than copper.

Example (our arithmetic): a 1 HP, 230 V pump set 200 feet down with a 60-foot run from the panel to the well has 260 feet of cable. That is past the 250 feet allowed on #14, so use #12, which allows 400. Have a licensed electrician size the wire and breaker for your case; the pump must be on a GFCI-protected circuit per Red Lion.

Constant Pressure vs a Standard Pump and Tank

The pumps above are standard: a pressure switch turns the motor on at one pressure and off at a higher one, and a tank holds water between cycles. Red Lion’s tank guide says to multiply the flow in GPM by 3 and go to the next larger size, and lists a 34-gallon tank for 8 GPM. Tank sizing and pre-charge are covered in our well pressure tank size and drawdown chart and our pressure switch guide.

A constant-pressure system varies the pump speed instead. Grundfos says its SQE pump with the CU 301 control unit and a pressure sensor holds a constant pressure while use changes, and sells constant-pressure packages with an 8-litre tank. The SQE has a permanent-magnet motor with a built-in frequency converter, soft start, dry-run protection and over- and under-voltage protection. It is a smaller pump: Grundfos gives a minimum borehole diameter of 76 mm and a maximum installation depth of 150 m below the static water level, and its models are rated in m3/h. Franklin makes a similar controller, SubDrive, and says a SubDrive needs only a small pressure tank. In that section Franklin also says its 2-wire motors require a minimum 20-gallon tank; we did not find that stated in Red Lion’s documents, so treat it as a Franklin SubDrive note. We did not find a Grundfos SQE listing we could verify as in stock and sold by Amazon or Grundfos on the check date, so we do not link one. If you want constant pressure, this is a job for a well contractor; our constant pressure well pump guide covers what those systems need.

Before You Buy

1. Confirm the casing. These pumps need a 4-inch or larger well, per Red Lion.
2. Get the driller’s report. It has the pumping water level and the well yield. Red Lion says to use it to set the pump.
3. Pick 115 V or 230 V, and 2-wire or 3-wire, before you order. Match the control box to the motor.
4. Budget the rest of the parts. Red Lion’s guide lists a pressure tank, a torque arrestor, a well seal or pitless adapter, and 1-inch discharge piping with the pump. Red Lion’s manual calls for schedule 40 galvanized pipe, or plastic per its maker’s depth and pressure rating.
5. Have a well developed and a pressure gauge. Red Lion warns that an undeveloped well often has abrasives that damage the pump. Our well pressure gauge picks help you verify cut-in and cut-out.

Installation Notes and When to Call a Contractor

Red Lion’s manual is clear on the points that fail most often. Attach a 3/16- to 1/4-inch steel safety cable. Install a torque arrestor just above the pump. Fasten the cable to the drop pipe every 10 feet and do not pinch it against the casing. Check continuity and insulation resistance with an ohmmeter and a megger. Install only positive-sealing check valves, never swing type. Never run the pump unless it is fully submerged. Do not set the pump below the screen or perforations unless there is enough water flow over the motor to cool it.

Pulling and setting a pump on 200 feet of pipe is heavy work with real risk: live 230 V, a cable that can be cut, and a pump that can be dropped down the well. Red Lion says the installation should be done by a licensed electrician or water systems contractor. Call a well or pump contractor if:

• the pumping water level is near or past 250 feet, where Red Lion says to call its technical line,
• the well is low-yielding or pumps down, where Red Lion says to consult a licensed water systems contractor about sizing,
• the water is sandy or does not clear in 30 minutes of the well test,
• the pump trips its overload, cycles quickly, or the control box is hot or burnt,
• you would have to splice cable or pull a pump from a deep well yourself.

FAQ

How deep can a 4-inch submersible well pump go?

Red Lion says its RL series works in 4-inch or larger drilled wells to a pumping water level of 250 feet, and to call its technical line past that. The RL12G10 lists a 434-foot shut-off head, but the shut-off head is the maximum lift at zero flow, not a working depth. Size from the flow table at your pumping level and pressure.

Should I buy a 2-wire or 3-wire submersible pump?

A 2-wire motor has its starting parts inside the motor. A 3-wire motor uses a control box above ground that holds the start capacitor and relay. Franklin Electric says 3-wire motors must be run with a matching control box and that running one without, or with the wrong box, can cause failure. Red Lion includes the box with its 1/2, 3/4 and 1 HP 3-wire pumps but not the 1.5 HP.

What size wire does a submersible pump need?

It depends on the motor and the length of the cable from the panel to the motor. Red Lion’s table, which matches Franklin’s, allows for a 5% voltage drop: for a 1 HP, 230 V motor, 250 feet on #14 copper, 400 feet on #12 and 630 feet on #10. Use the maker’s table, and have an electrician size the circuit.

How big a pressure tank do I need with a submersible pump?

Red Lion’s guide says to take the pump flow in GPM, multiply by 3, and go to the next larger tank size, so 8 GPM gives 24 gallons and a 34-gallon tank. Red Lion recommends a tank with a bonded diaphragm, air cell or water bag, and lists an undersized tank as a cause of rapid cycling.

Do I need a check valve with a submersible pump?

Yes. Red Lion says most 4-inch pumps have a check valve built in, and to install only positive-sealing check valves, never swing type, with one in the discharge line within 25 feet of the pump and below the drawdown level. On a well deeper than 200 feet, Red Lion says to add one every 200 feet. Backspin from a missing or failed check valve damages the pump.

Why Trust Plumbing Picks

Plumbing Picks is written by a licensed Georgia journeyman plumber. Every size, rating, dimension and spec on this page comes from the manufacturer pages and documents listed below, which we opened and read, or from the Amazon listing we link; nothing here comes from hands-on testing. Each linked product was shipped or sold by Amazon, new and in stock, when we checked on September 28, 2026. Where a link goes to Amazon we may earn a commission at no extra cost to you. Nobody pays to be included here. More on who writes this and how we pick.

Sources

• Red Lion: 4″ submersible well pumps, RL series (product page)
• Red Lion: RL series spec sheet (performance table, linked from the RL series page)
• Red Lion: deep well submersible pump owner’s manual (106720101 Rev. 003)
• Red Lion: product catalog 996508 (cable selection and glossary)
• Red Lion: Easy Guide to Pump & Tank Selection (1-2-3 guide)
• Franklin Electric: AIM manual, 60 Hz submersible systems, 2023 edition (copy hosted by a distributor)
• Grundfos: SQ, SQE submersible pumps data booklet
• Grundfos: SQ, SQE installation and operating instructions
• Amazon listings for the Red Lion RL12G10-3W2V, RL12G05-2W2V, RL12G05-2W1V and RL22G10-3W2V (linked above)

Bottom Line

Under 25 feet to water, use a shallow well pump; deeper, use a submersible. For most houses the Red Lion RL12G10-3W2V is the pump to buy, the RL12G05-2W2V is the no-control-box pick for a cabin, and the RL22G10-3W2V is for high demand on a well that can supply it. Size from the flow table at your pumping level and pressure, take the wire size from the maker’s table, and call a well contractor for anything deep, low-yielding or hard to pull.