Shallow Well Pump: 5 Jet Pumps for Water Within 25 Feet

A shallow well jet pump sits above ground and pulls water up by suction. Goulds puts the limit at 25 ft of lift, and that 25 ft includes friction loss in the suction pipe, not just the vertical distance. If your pumping water level stays inside that, compare pumps by the flow they make at your lift and mid-cycle pressure. For a 30/50 switch, that’s 40 psi. Of the five pumps here, the Red Lion RJS-100-PREM lists the most water at a full 25 ft lift, 11.5 gpm. If the water can drop below 25 ft in a dry season, buy a convertible pump instead.

The 25-foot rule, friction included

Goulds’ jet pump manual limits shallow-well systems to a maximum suction lift of 25 ft, counting vertical lift plus friction in the suction piping. A shallow system has one pipe going to the well. Above 25 ft, you need a deep-well jet, which uses two pipes (twin-pipe) or a packer assembly in the well.

Friction is why a well with water at 20 ft can still struggle. Goulds says the suction pipe should be at least as large as the pump’s suction port, typically 1-1/4 in. Smaller pipe raises friction and the effective lift. On horizontal offsets over 50 ft, it recommends pipe larger than the suction port. It also says not to put filters on the suction side, because a dirty filter increases effective lift and can starve the pump. If you install a throttling valve to protect a low-yield well, Goulds says not to throttle past 22 in Hg of vacuum, which equals 25 ft of lift.

Shallow-only vs convertible

• Shallow-well jet pumps have the jet built in and stop at 25 ft. The Wayne SWS100, Red Lion RJS-100-PREM and Flotec FP4012-10 are this type.
• Convertible jet pumps run as shallow pumps with a shallow-well adapter or ejector, or as deep-well pumps with a jet assembly down the well. Red Lion’s RJC-75-PREM is rated as one-pipe shallow under 25 ft and two-pipe deep from 25 to 90 ft. Wayne rates the CWS75 for 0–90 ft and says the jet assembly is sold separately.

A convertible costs you some flow at shallow depths but gives you a path if the water table falls. Past about 90 ft, see submersible well pumps.

The five pumps compared

All flows are at 40 psi, converted to gpm where the maker publishes gallons per hour.

	Red Lion RJS-100-PREM	Wayne SWS100	Red Lion RJC-75-PREM	Wayne CWS75	Flotec FP4012-10
Type	Shallow	Shallow	Convertible	Convertible	Shallow
HP	1	1	3/4	3/4	1/2
Voltage / amps	115/230 V; 17.6 A / 8.8 A	115/230 V; amps not stated	115/230 V; 17.6 A / 8.8 A (as listed)	115/230 V; amps not stated	115/230 V; 9.4 A full load
gpm near the surface	16.8 at 5 ft	12.3 at 5 ft	12.2 at 5 ft	13.0 at 0 ft	6.4 at 10 ft (pressure not stated)
gpm at 20–25 ft	11.5 at 25 ft	8.2 at 25 ft	8.9 at 25 ft (two pipes)	8.5 at 20 ft	Not stated
gpm at 60 ft	Not rated	Not rated	3.7	3.1	Not rated
Deepest rated lift	25 ft	25 ft	90 ft	90 ft	25 ft
Max pressure	65 psi (5 ft lift)	Not stated	68 psi (5 ft, one pipe)	Not stated	77 psi
Body	Cast iron; thermoplastic impeller	Cast iron volute	Cast iron; thermoplastic impeller	Cast iron volute	Thermoplastic
Switch	30/50 included	30–50 preset	30/50 plus gauge	30–50 preset	30/50 pre-wired
Certifications	CSA to UL 778 and CSA 108; NSF/ANSI 372	Not stated	Not stated	Not stated	Not stated
Warranty	Not stated in page text	Not stated	Not stated in page text	Not stated	1-year limited
Relative cost	$	$	$	$	$

Sources: Red Lion, Wayne and Flotec product pages. Wayne figures converted from GPH (divide by 60).

For scale, the Nebraska DWEE sizing worksheet estimates peak household demand as outlets running at once times 3 gpm. Two fixtures at once is about 6 gpm, and three is about 9 gpm. At a full 25 ft lift, only the RJS-100-PREM clears 9 gpm at 40 psi on paper.

Priming and suction piping

Goulds defines priming as filling the pump and suction pipe with water. Its manual gives the steps and the reasons a pump won’t hold prime:

• Fill through the discharge tee (a tee with a plug or gauge in its top port). On shallow pumps, remove the small 1/8 in vent plug so air can escape while you fill. Wayne’s SWS100 and CWS75 have a dedicated priming port on the volute.
• Expect it to take a while. Goulds says it can take several minutes to prime, depending on depth to water and pipe size and length.
• Pumps don’t hold prime; the piping and check valves do. Eliminate high spots and dips that trap air, and run the suction line straight or sloping upward to the pump. Double-clamp barbed fittings on poly pipe, because any air leak means the pump will not make pressure.
• Use a foot valve on the drop pipe in wells 2 in or larger, set at least 5 ft off the bottom of a clean well. On sand points or driven wells, use an in-line check valve near the well head and the casing as the suction pipe.
• Never run the pump dry. Goulds says damage will result and the warranty will be voided. Always disconnect and lock out power before working on the pump, motor or switch.

If a pump that used to work has started losing prime, see well pump not working.

Tank, switch and placement

Goulds says the pump must be within 4 ft of the tank to prevent switch chatter. Nothing should sit between the pump and tank except a fully open gate valve or a full-port ball valve. Check the tank’s air precharge with the tank empty, and set it 2 psi below the switch’s cut-in. That’s 28 psi on a 30/50 switch. Keep the pump where it won’t freeze, and keep water under 140°F, the limit Goulds and Flotec both state. Our well pressure tank guide covers tank sizing for a jet pump.

The picks

Red Lion RJS-100-PREM: most flow at a full 25 ft lift

It lists 11.5 gpm at 40 psi and 25 ft, and 13.3 gpm at 30 psi. It’s the only pump here with stated electrical-safety and lead-free certifications. The cons: a 17.6 A draw at 115 V (8.8 A at 230 V), so check the circuit. Maximum pressure falls to 55 psi at 25 ft of lift, which is little headroom over a 50 psi cut-out. The warranty is shown only as a graphic on the page.

Wayne SWS100: 1 HP shallow pump with a dedicated priming port

It has a cast iron volute with a dedicated priming port, a preset switch and dual-voltage wiring. Its flow at 25 ft and 40 psi (about 8.2 gpm) is lower than the Red Lion’s, and at 50 psi it drops to about 3.4 gpm. The page doesn’t state amps, maximum pressure, certifications or warranty.

Red Lion RJC-75-PREM: if the water level may fall below 25 ft

It runs as a one-pipe shallow pump under 25 ft and as a two-pipe deep-well jet from 25 to 90 ft. At 40 psi it lists 8.9 gpm at 25 ft and 3.7 gpm at 60 ft, and at 90 ft only 1.3 gpm. One data point to confirm: Red Lion’s page lists the same 17.6 A / 8.8 A draw for this 3/4 HP pump as for its 1 HP RJS-100-PREM. Check the motor nameplate or owner’s manual before sizing the circuit.

Wayne CWS75: convertible with a full 0–90 ft flow table

Wayne’s table goes every 10 ft. At 40 psi it shows about 10.5 gpm at 10 ft, 6.8 gpm at 30 ft and 3.1 gpm at 60 ft, and zero at 90 ft. At 30 psi it still makes about 0.9 gpm at 90 ft. The cons: the jet assembly is required and sold separately, and amps, certifications and warranty aren’t stated.

Flotec FP4012-10: for light loads on a 1/2 HP budget

It has a thermoplastic body, an 8 gpm maximum capacity, 6.4 gpm at 10 ft of lift, a 77 psi maximum and a 15 A recommended breaker. It fits a cabin, a single bathroom or garden use better than a full household. Flotec gives no flow at a stated pressure, and the warranty is 1 year.

How to choose

1. Measure the pumping water level, not just the static level, and add suction-pipe friction. Over 25 ft total means a convertible or a submersible.
2. Estimate peak demand at 3 gpm per fixture running at once, and compare it to the 40 psi column at your lift.
3. Check the circuit. A 1 HP jet pump at 115 V draws 17.6 A (Red Lion). Switching to 230 V halves that.
4. Plan the suction side before buying: pipe size, foot valve or check valve, and a priming tee.

The well pump guide covers how jet pumps compare with submersibles, and well pump replacement cost covers what a contractor install involves.

Who should skip all of these

• Drilled wells with deep water. Past 25 ft a shallow pump won’t lift, and past 90 ft a convertible won’t either. A submersible is the usual answer.
• Wells that run low in dry spells. A drawdown past 25 ft costs a shallow pump its prime. Pick a convertible with room to go deeper.
• Anyone who doesn’t want to deal with priming. Every jet pump here has to be primed after installation or after losing suction.

Sources

1. Goulds Water Technology — Jet Pumps Installation, Operation and Troubleshooting Manual (IM102R11, 2022)
   25 ft lift including friction; shallow, convertible and deep-well jet types; priming steps; suction piping, foot valve, 22 in Hg limit; pump within 4 ft of tank; 140°F; never run dry
2. Red Lion — Premium cast iron shallow well jet pumps (RJS-PREM series)
   RJS-100-PREM flow table, max pressure and head, amps by model, certifications
3. Red Lion — Premium cast iron convertible jet pumps (RJC-PREM series)
   RJC-75-PREM flow table by lift and pipe count, shallow/deep ranges, amps, max pressure
4. Wayne — SWS100 1 HP cast iron shallow well jet pump
   GPH by depth at 30/40/50 psi; 0–25 ft; priming port; ports; voltage
5. Wayne — CWS75 3/4 HP cast iron convertible jet well pump
   GPH by depth 0–90 ft at 30/40/50 psi; jet assembly sold separately; ports
6. Pentair Flotec — FP4012-10 thermoplastic shallow well jet pump, 1/2 HP
   8 gpm max, 6.4 gpm at 10 ft, 25 ft max lift, 77 psi, 9.4 A, 140°F, 1-year warranty
7. Nebraska Department of Water, Energy and Environment — Water Systems Sizing and Selection worksheet
   Peak demand as simultaneous outlets x 3 gpm