1 HP Well Pumps

1 HP well pumps are self-priming centrifugal or jet-style pumps rated at one horsepower, designed to draw water from a well and pressurize a home's plumbing system for consistent, reliable water delivery. At the 1 HP rating, these pumps deliver meaningfully more flow than fractional-horsepower models: the Grundfos JP PS 16 10 187, for example, reaches a maximum flow of 21 GPM with a max head of 187 feet, making it well-suited for whole-home supply in residential and light agricultural settings.

1 HP well pumps split into two main installation types: shallow well pumps for water tables at 25 feet or less, and convertible jet pumps that handle wells from 0 to 90 feet depending on the jet assembly used. Brands like Wayne, Little Giant, and Grundfos each bring their own construction approach to the category, from cast iron casings and stainless steel components to dual-voltage motors wired for flexibility in the field. For any application where a homeowner, farm, or cabin needs pressurized domestic water from a private well, a 1 HP pump is the workhorse of the lineup.

Shallow Well Jet Pumps

Shallow well jet pumps are surface-mounted, self-priming centrifugal pumps that draw water through a single suction pipe from a water source no more than 25 feet below the pump. Plumbers and homeowners install shallow well jet pumps when the static water level is consistently within that 25-foot window. The Wayne SWS100 is a cast iron 1 HP shallow well jet pump rated to move up to 513 GPH at 50 PSI, with a dual-voltage 115V/230V motor factory-set at 115V and a pressure switch preset at 30-50 PSI for automatic operation. The Little Giant JP-100-C fills the same niche with a cast iron casing and seal plate, A.O. Smith higher-than-standard NEMA service factor motor, Square D pressure switch preset at 30-50 PSI, and 1-1/4" suction paired with 1" NPT discharge.

Convertible Jet Pumps

Convertible jet pumps are surface-mounted pumps that handle both shallow and deep well applications by swapping jet assemblies, with effective lift reaching up to 90 feet in deep well configuration. Installers choose convertible jet pumps when well depth is between 25 and 90 feet, or when a single pump needs to serve either application depending on the site. The Wayne CWS100 is a 1 HP convertible jet pump with cast iron construction, a max flow of 588 GPH at 50 PSI, and dual voltage 115V/230V; the jet assembly is sold separately and is required for operation. The Little Giant JPC-100-C is a 1 HP convertible jet pump rated for wells up to 90 feet, also featuring a Square D pressure switch and a cast iron body built for long-term residential and farm use.

Stainless Steel Jet Pump Systems

Stainless steel jet pump systems combine a corrosion-resistant pump housing with a pre-charged pressure tank, offering an integrated approach suited to applications where mineral-heavy water or outdoor exposure would accelerate corrosion on standard cast iron units. The Grundfos JP PS 16 10 187 is a 1 HP single-stage stainless steel shallow well jet pump with an integrated pressure switch, max flow of 21 GPM, and a max head of 187 feet, operating on dual voltage 115/230V at 60 Hz. Stainless steel construction also simplifies maintenance intervals in corrosive water conditions compared to painted or uncoated cast iron alternatives.

The first question when selecting a 1 HP well pump is well depth. If the static water level sits within 25 feet of the pump, a shallow well jet pump handles the job cleanly. For depths between 25 and 90 feet, a convertible jet pump with the appropriate ejector or deep well jet assembly is the right specification. Get that wrong and no amount of motor horsepower compensates for the physics of suction lift.

Voltage is the next call. Most 1 HP well pumps in this category run on dual voltage 115V/230V motors, which gives the installer flexibility on the panel side. Wayne SWS100 and CWS100 models ship factory-set at 115V; the Grundfos JP PS 16 10 187 handles both 115V and 230V at 60 Hz. Confirm the available service before ordering, especially for older homes where 230V service may not run to the pump location.

Flow rate and system demand determine whether a 1 HP well pump can support the load. A typical single-family home with two to three bathrooms, a washing machine, and a dishwasher running simultaneously can require 8 to 12 GPM. The Wayne CWS100 moves up to 588 GPH (roughly 9.8 GPM) at 50 PSI, while the Grundfos JP PS 16 10 187 reaches 21 GPM maximum flow. When asking how to size a 1 HP well pump for a home, start with peak simultaneous fixture demand, not average daily use.

Construction material matters for long-term durability. Cast iron housings from Wayne and Little Giant handle standard residential water well conditions well. For sites with aggressive water chemistry, the stainless steel construction of the Grundfos JP PS 16 10 187 reduces the risk of casing corrosion over time. Pressure switch settings also affect system longevity: most 1 HP well pumps in this category ship with a 30-50 PSI factory preset, which suits residential plumbing fixtures without over-cycling the pump motor.

FAQs

What is the difference between a shallow well jet pump and a convertible jet pump at 1 HP?

The difference between a shallow well jet pump and a convertible jet pump is installation depth range. A 1 HP shallow well jet pump, such as the Wayne SWS100 or Little Giant JP-100-C, handles water tables up to 25 feet below the pump. A convertible jet pump, such as the Wayne CWS100 or Little Giant JPC-100-C, can serve wells from 0 to 90 feet depending on the jet assembly attached. Shallow well jet pumps use a single suction pipe; convertible jet pumps require a separate jet assembly to operate in deep well mode.

How many GPM does a 1 HP well pump deliver?

How many GPM a 1 HP well pump delivers depends on the model and the operating pressure. The Grundfos JP PS 16 10 187 reaches a maximum flow of 21 GPM with a max head of 187 feet. The Wayne SWS100 moves up to 513 GPH (approximately 8.6 GPM) at 50 PSI for shallow well applications. Actual flow at the fixture is lower than the pump's rated max, since friction losses in the pipe system and operating pressure both reduce delivered GPM.

Does a 1 HP convertible jet pump come with the jet assembly included?

Whether the jet assembly is included with a 1 HP convertible jet pump varies by model. The Wayne CWS100 ships without a jet assembly; the assembly is sold separately and is required for the pump to operate in either shallow or deep well mode. Installers should confirm which jet assembly matches the well casing diameter before ordering: Wayne offers assemblies for 2-inch single-drop pipe wells and 4-inch double-drop pipe wells.

What voltage does a 1 HP well pump require?

Most 1 HP well pumps in this category run on dual-voltage motors that accept either 115V or 230V single-phase power. The Wayne SWS100, Wayne CWS100, and Little Giant JP-100-C all ship factory-set at 115V but can be rewired in the field for 230V service. The Grundfos JP PS 16 10 187 operates on dual voltage 115/230V at 60 Hz. Confirming the available panel voltage before installation avoids the need to rewire after the pump is in place.

How deep a well can a 1 HP well pump handle?

How deep a well a 1 HP well pump can handle depends on the pump type. A 1 HP shallow well jet pump, such as the Wayne SWS100 or Little Giant JP-100-C, is rated for water tables up to 25 feet below the pump. A 1 HP convertible jet pump, such as the Wayne CWS100 or Little Giant JPC-100-C, handles wells from 0 to 90 feet in depth when fitted with the appropriate jet assembly. Wells deeper than 90 feet require a submersible deep well pump rather than a surface-mounted jet pump.