Davey's Horizontal Multistage Water Pump With Pressure Switch - HM270-19P
Key features:
- Standard automatic pressure system type.
- Suitable for 4 storey households and offices.
- For household, garden, farming, and agricultural use.
- 24 months warranty for pump, motor & controller.
(24 + 6 additional months with e-Warranty scheme) - Fixed pressure setting on every usage.
- Easy installation, no setting required.
Classified As:
Overview of Davey's Horizontal Multistage Water Pump With Pressure Switch - HM270-19P
The largest model of the HM Horizontal Multistage series in Davey Water Products Pty Ltd. The HM270-19P is perpetually built for the commercial, industrial, and heavy-duty applications, sending large volumes of pressure far across with its integrated and motorised engine. In household applications, this Horizontal Multistage pump is capable of sending fluids for up to four storey buildings, making sure that the same even pressure can be felt afar despite the installation onto the wide accessible range of a water system found. With the HM270-19P, the uniqueness of this centrifugal pump is that it’s fastened with a pressure switch, elevating the traditional and classical pressuring machine and this is paired to work alongside a pressure tank to eliminate the continuous pump cycling.
Complete hydraulic parts are built onto the Horizontal Multistage electropump, and this is conducted under automated lean manufacturing of Davey’s production line to assemble laser-accurate precision of components. After any batch construction, all HM270-19P runs through a rigorous testing to ensure the effectiveness and operation of its implementation, and this prioritises the consumer’s satisfaction as the utility of the pump’s use remain as is. And like the nature of its name, the HM270-19P Horizontal Multistage water pump has clean fluids entering through the inlet on a flat-level arrangement. With multiple stages of impellers and diffusers lined up its volute, water swirls onto its body and causes a steady rise in pressure before fluids come gushing out from the outlet of the Horizontal Multistage pump.
SS304 version of stainless steel can be seen making up the bits and pieces of the HM270-19P, while various O-rings of varied sizing are attached to secure the fittings to prevent unnecessary hydration leaks. For the shaft itself, this centrifugal pump has the premium grading of SS316 version of stainless steel used, ensuring longevity and durability for the years to come without reducing it to failure with its high resistance to corrosion. The HM270-19P Horizontal Multistage water pump comes with a totally-enclosed, fan-cooled engine (or what is known as a TEFC motor) as a one-piece secured structure to cool its mechanism down, but also as a way to prevent foreign meddling from touching the engine.
Warranty: Two years of manufacturing warranty is guaranteed, and is backed by another 6 months for the HM270-19P Horizontal Multistage water pump should the e-Scheme be signed up for.
HM270-19P's Method of Identification
To support seamless product traceability across manufacturing, inventory management, and global distribution, the Horizontal Multistage HM270-19P follows the standardised product naming convention established by Davey Water Products and Waterco. This structured model designation also enhances quality assurance, simplifies product identification, and supports ISO-compliant quality management and auditing processes.
The HM270-19P model designation is interpreted as follows:
1) HM – Identifies the Horizontal Multistage pump series.
2) 270 – Represents the nominal flow rate at the pump’s Best Efficiency Point (BEP), rated at 270 litres per minute (L/min).
3) 19 – Denotes the 1.9 kW motor power rating.
4) P – Indicates the pump is supplied with an integrated pressure switch.
The HM270-19P model designation provides a clear and meaningful reference to the pump’s key performance and configuration specifications.
The “HM” prefix identifies the pump as part of Davey’s Horizontal Multistage series. The number “270” denotes the pump’s nominal flow rate at its Best Efficiency Point (BEP), delivering 270 litres per minute (L/min). The “19” indicates the 1.9 kW motor power rating, while the suffix “P” confirms that the pump is equipped with an integrated pressure switch.
Beyond describing the pump’s technical specifications, the HM270-19P model designation and unique Stock Keeping Unit (SKU) support efficient product identification throughout Davey Malaysia’s manufacturing, warehousing, distribution, and after-sales operations. A standardised naming system streamlines inventory management, improves order accuracy, accelerates warehouse processing, and strengthens product traceability across the supply chain.
For installers, plumbers, and service technicians, the model designation provides a reliable means of identifying the exact pump installed at a property. This simplifies maintenance, ensures the correct replacement parts are specified, and enables servicing to be completed accurately and efficiently, helping to maximise the long-term performance and operational lifespan of the HM270-19P Horizontal Multistage water pump.
Attachment
Mechanical Pressure Switch
As an alternative to the Torrium2 Intelligent Pressure Controller, the HM270-19P can also be configured with a conventional mechanical pressure switch. This cost-effective solution provides reliable automatic pump control by operating solely in response to changes in system water pressure.
Unlike electronic pump controllers, a mechanical pressure switch does not incorporate sensors, microprocessors, or adaptive control technology. Instead, it uses a spring-loaded diaphragm and electrical contacts to monitor pressure and automatically start or stop the pump at pre-set pressure levels.
The pressure switch operates using two fixed pressure thresholds: the cut-in pressure and the cut-out pressure. When system pressure drops below the cut-in setting due to water demand, the switch closes the electrical circuit and starts the pump. The pump continues operating as it restores pressure throughout the system until the cut-out pressure is reached. At this point, the switch opens the electrical circuit, stopping the pump and maintaining the desired operating pressure until water is required again.
Although simpler in design than an electronic controller, a mechanical pressure switch offers dependable automatic operation and remains a practical, economical solution for a wide range of residential and light commercial water pressure applications.
Example of Mechanical Pressure Switch Operation
- Below 20 psi (1.4 bar): System pressure falls below the cut-in setting, causing the HM270-19P to start automatically.
- Between 20 and 40 psi (1.4–2.8 bar): The pump continues operating to restore and maintain water pressure throughout the system while water is being used.
- At 40 psi (2.8 bar): Once the cut-out pressure is reached, the mechanical pressure switch opens the electrical circuit, stopping the pump until the next demand for water.
Important: A pressure tank is required when operating the HM270-19P with a mechanical pressure switch. The pressure tank stores a reserve of pressurised water, reducing frequent pump starts and stops caused by small fluctuations in water demand. This minimises pump cycling, improves overall system efficiency, and helps extend the service life of the pressure switch, pump, and associated system components.
Pressure Tank
A pressure tank is a sealed vessel that stores water under pressure using compressed air. When used in conjunction with a mechanical pressure switch, it provides a reserve of pressurised water that reduces the frequency of pump starts and stops. This minimises pump cycling, improves overall system efficiency, and helps extend the service life of the pump and its associated components.
Inside the pressure tank are two separate chambers, separated by a durable rubber diaphragm. One chamber contains water, while the other is pre-charged with compressed air. As the Horizontal Multistage pump fills the tank, the incoming water compresses the air chamber, storing energy in the form of hydraulic pressure.
When a tap, shower, or other water outlet is opened, the compressed air forces water from the tank into the plumbing system, allowing water to be supplied without the pump starting immediately. As water is drawn from the tank, the system pressure gradually decreases. Once it reaches the mechanical pressure switch’s preset cut-in pressure, the Horizontal Multistage pump automatically starts to replenish the tank and restore the system to its designated operating pressure. The pump continues operating until the cut-out pressure is reached, at which point the pressure switch stops the pump. This operating cycle maintains consistent water pressure, reduces unnecessary pump cycling, and helps minimise mechanical wear, extending the service life of the pumping system.
Certification
Davey’s Horizontal Multistage water pumps, including the HM270-19P, are designed and manufactured to comply with a range of internationally recognised standards and certifications. These accreditations demonstrate the product’s safety, quality, reliability, and performance while supporting regulatory compliance and access to global markets.
Compliance with recognised international standards enables Davey to supply its Horizontal Multistage pump range worldwide while meeting applicable legislative and technical requirements. These certifications provide customers, engineers, and installers with confidence that each pump has been designed, manufactured, and, where applicable, independently assessed in accordance with established engineering and quality benchmarks.
Beyond meeting regulatory requirements, these certifications reflect Davey’s commitment to continuous product improvement and quality assurance. Every stage of the design, manufacturing, and testing process is carefully controlled to ensure the HM270-19P delivers dependable hydraulic performance, electrical safety, mechanical reliability, and long-term operational durability.
SGS Verification: Products verified by SGS (Société Générale de Surveillance) undergo independent assessment to confirm compliance with applicable standards and the manufacturer’s specified performance criteria. For the Horizontal Multistage pump range, this may include evaluations of hydraulic performance, material quality, electrical safety, and overall product reliability. Independent verification provides additional assurance that the pump performs as specified while meeting recognised quality and safety expectations.
European Ecodesign Compliance: Davey’s Horizontal Multistage pumps are designed to comply with applicable European Ecodesign Regulations governing the energy efficiency of water pumps intended for the European market. These regulations establish minimum energy performance requirements to encourage more efficient and environmentally responsible pump design.
Compliance with the Ecodesign framework helps deliver several key benefits:
- Improved hydraulic efficiency
- Reduced electricity consumption
- Lower operating costs
- Reduced greenhouse gas emissions
- Enhanced environmental sustainability
Compliance with internationally recognised standards also helps ensure that pumps achieve high levels of safety, performance, and reliability, reducing the risk of mechanical failure, water leakage, and electrical hazards throughout their operational life.
International Electrotechnical Commission (IEC): The International Electrotechnical Commission (IEC) develops globally recognised standards for electrical and electronic equipment. Compliance with applicable IEC standards ensures that the electrical systems used in Davey’s Horizontal Multistage pumps are designed, manufactured, and tested to meet internationally accepted safety and performance requirements.
Relevant IEC standards cover areas including:
- Electric motor safety
- Electrical insulation and protection
- Control system performance and reliability
- Electrical performance testing
- Electromagnetic compatibility and integration with auxiliary equipment, including Variable Frequency Drives (VFDs)
Adherence to applicable IEC standards helps minimise the risks associated with electric shock, overheating, short circuits, and fire, while ensuring safe, reliable electrical performance across a wide range of operating and installation environments.
Australian Standards: As an Australian manufacturer, Davey designs its products in accordance with applicable Australian Standards, which are internationally recognised for promoting product safety, quality, and performance. Compliance with these standards reinforces customer confidence throughout Australia, New Zealand, Southeast Asia, and other global markets by demonstrating that the HM270-19P has been engineered to meet rigorous safety and engineering requirements.
- AS 4020:2005 – Products for Use in Contact with Drinking Water: One of the most important standards applicable to potable water systems is AS 4020:2005, which assesses materials and components that come into contact with drinking water. The standard evaluates whether these materials leach harmful substances, impart undesirable taste, colour, or odour, or otherwise adversely affect water quality. Compliance with AS 4020:2005 demonstrates that the wetted materials used within the Horizontal Multistage pump are suitable for continuous contact with potable water, helping to ensure water quality is maintained throughout normal operation.
Standards New Zealand: For distribution within New Zealand, Davey products are designed to comply with relevant requirements recognised by Standards New Zealand. Meeting these requirements supports regulatory acceptance while providing customers with confidence that the products have been developed to satisfy New Zealand’s expectations for safety, quality, and performance.
ISO 9001:2015 – Quality Management Systems: ISO 9001:2015 is an internationally recognised standard for Quality Management Systems (QMS). Certification demonstrates Davey’s commitment to consistently manufacturing water pumps and related products that meet customer expectations and applicable regulatory requirements.
The standard requires a structured approach to quality control, process management, and continuous improvement throughout the manufacturing lifecycle. This helps ensure consistent product quality, reliability, and performance across every production batch.
ISO 14001 – Environmental Management Systems: ISO 14001 recognises organisations that implement effective environmental management systems. For Davey, certification reflects a commitment to reducing environmental impact throughout manufacturing operations by improving resource efficiency, minimising waste, supporting recycling initiatives where practical, and continuously enhancing sustainable production practices.
TÜV SÜD Certification: The HM270 Horizontal Multistage series undergoes independent assessment by TÜV SÜD, one of the world’s leading product testing and certification organisations. TÜV SÜD certification provides additional assurance that the pump has been evaluated through rigorous testing processes covering safety, quality, performance, and compliance with applicable engineering requirements.
Collectively, these certifications demonstrate Davey’s commitment to engineering excellence, product safety, environmental responsibility, and manufacturing consistency. Beyond regulatory compliance, they represent independent recognition that the HM270-19P has been designed, manufactured, and tested in accordance with internationally recognised standards.
For customers, installers, engineers, and distributors, these accreditations provide confidence that every Davey Horizontal Multistage water pump delivers reliable performance, dependable operation, and long-term quality across a wide range of installation environments.
Constant-Speed TEFC Motor
The HM270-19P is powered by a Totally Enclosed Fan Cooled (TEFC) motor designed to deliver reliable, consistent performance for residential and light commercial water pressure applications. Operating at a fixed speed, the motor provides dependable operation while offering enhanced protection against dust, dirt, moisture, and other environmental contaminants. This robust construction improves durability and reduces maintenance requirements throughout the motor’s service life.
The fully enclosed motor design prevents external contaminants from entering and affecting critical electrical components. Heat generated during operation is effectively managed by an external cooling fan mounted to the motor shaft, which continuously circulates air across the motor housing to dissipate heat. This cooling method maintains optimal operating temperatures while keeping the internal windings isolated from the surrounding environment, contributing to improved reliability and long-term performance.
Within the HM270-19P, the hydraulic section, where water is transferred through the pump, is separated from the motor assembly by a mechanical seal and backplate system. This design prevents water from entering the motor compartment during normal operation, protecting the electrical components from moisture and helping ensure safe, reliable performance. Water ingress would generally only occur in the unlikely event of a mechanical seal or backplate failure.
Plug-And-Use Convenience: The HM270-19P is supplied as a complete pump and motor assembly, providing a simple installation process with minimal setup requirements. Once connected correctly to the plumbing system and electrical supply, the pump is ready for operation without the need for additional motor configuration or commissioning procedures. This plug-and-use design reduces installation time and provides added convenience for both homeowners and professional installers.
Proven TEFC Motor Technology: The HM270-19P is equipped with a Totally Enclosed Fan Cooled (TEFC) motor, a proven motor design recognised for its durability, reliability, and consistent performance across a wide range of industrial and water pumping applications.
The motor’s enclosed construction provides protection against dust, dirt, moisture, and other environmental contaminants, while the external cooling fan efficiently removes heat generated during operation. By keeping critical internal components protected from external conditions, the TEFC design reduces maintenance requirements and supports reliable performance over an extended service life.
Lower Maintenance, Lower Operating Costs: The combination of a robust TEFC motor, corrosion-resistant hydraulic components, and Davey’s engineering expertise helps deliver lower total ownership costs throughout the HM270-19P’s operating life. Reduced exposure to contaminants, durable construction, and reliable operation help minimise routine servicing requirements and limit wear caused by frequent pump cycling.
Whether installed in a residential property, shop lot, or light commercial application, the HM270-19P is designed to provide long-term value through dependable performance, reduced downtime, and extended service life.
Inlet Sizing
The HM270-19P is equipped with a two inch suction inlet connection designed to support efficient water intake into the pump’s hydraulic system. While the pump is supplied with a standard inlet size, compatible connectors and adaptors can be used to accommodate different piping arrangements, providing installation flexibility to suit various site requirements.
The suction inlet plays an essential role in centrifugal pump operation by providing the entry point for water before it is pressurised and delivered throughout the property. Correct inlet sizing, appropriate pipe selection, and proper installation practices help maintain smooth water flow, minimise hydraulic restrictions, and support efficient pump performance.
As part of Davey’s Horizontal Multistage series, the HM270-19P is engineered for clean water applications, providing reliable and consistent water pressure across residential, office, and light commercial environments. When installed correctly, the pump delivers efficient water transfer, stable performance, and dependable operation to support the needs of larger properties and higher-demand water systems.
One-Directional Flow Design: The Davey HM270-19P Horizontal Multistage pump utilises a unidirectional flow design, where the electric motor drives a series of impeller stages to generate the pressure required to draw water into the pump and efficiently transfer it through the hydraulic system. This controlled flow path enables consistent pressure delivery while maintaining smooth, stable movement of clean water throughout the application.
Reduced Hydraulic Resistance: In centrifugal pump systems, correctly sized inlet connections play an important role in reducing hydraulic losses and maintaining efficient water flow. A larger suction inlet diameter can help minimise frictional resistance, improve water intake conditions, and support smoother hydraulic performance by allowing water to enter the pump with fewer restrictions.
Achieving the best pump performance requires the correct combination of inlet sizing, pipe configuration, and installation practices. Proper system design helps maximise hydraulic efficiency, maintain reliable operation, and support the long-term performance of the HM270-19P.
The following table summarises the HM270-19P suction inlet and discharge outlet specifications:
| 240V Single Phase Models | ||
|---|---|---|
| Product Code | Ports | |
| Suction BSP | Discharge BSP | |
| HM270-19 | 2 inch F (50.8mm) | 1 1/2 inch M (38.1mm) |
Volute
The volute of the HM270-19P Horizontal Multistage pump forms the outer hydraulic casing that houses and supports the internal impeller and diffuser assemblies. While the external casing has a cylindrical appearance, the internal flow passage is precisely engineered with a spiral-shaped geometry to optimise water movement and hydraulic efficiency throughout the pump.
Constructed from durable, high-quality composite materials, the volute is designed to withstand continuous operating conditions while maintaining long-term structural strength, reliability, and consistent hydraulic performance.
The volute plays a critical role in the pump’s efficiency by collecting and directing water as it exits each impeller stage. Its spiral design gradually converts the velocity energy of the moving water into pressure energy before guiding the flow towards the discharge outlet. This controlled flow transition helps minimise turbulence, improve pressure generation, and maintain stable water delivery throughout the system.
Through the combination of durable construction and precisely engineered hydraulic geometry, the HM270-19P volute supports reliable pressure delivery, improved hydraulic efficiency, and consistent performance across a wide range of residential and light commercial applications.
In addition, the robust volute casing provides an added layer of protection for the hydraulic assembly by helping shield internal components from external contaminants. This protective design supports cleaner water delivery, reduces the potential for premature component wear, and contributes to the long-term reliability and durability of the pumping system during continuous operation.
Energy Transfer Process: In the HM270-19P Horizontal Multistage pump, the energy transfer process begins with the electric motor driving the impeller assembly, creating the rotational energy required to move water through the hydraulic stages. As water enters the pump, each impeller transfers energy to the fluid, increasing its velocity and directing it outward through centrifugal force into the surrounding diffuser and volute passages.
As the water flows through the volute, the expanding flow path allows the kinetic energy generated by the impellers to be progressively converted into pressure energy. This reduction in fluid velocity results in an increase in pressure, creating a stable and controlled discharge flow at the pump outlet.
This hydraulic conversion process is based on fundamental fluid dynamics principles, including the relationship between velocity, pressure, and energy described by Bernoulli’s equation. Through this carefully engineered energy transfer process, the HM270-19P achieves efficient pressure generation and reliable water delivery across a range of applications.
Self-Priming Performance: During operation, the HM270-19P requires the pump chamber and hydraulic passages to be filled with water to establish stable and continuous flow through the impeller stages. Effective removal of trapped air is essential, as air pockets within the hydraulic system can disrupt water movement, reduce pumping efficiency, and lead to inconsistent operating conditions.
Excessive air accumulation around the impeller area may increase the risk of cavitation, a condition where vapour bubbles form and collapse due to rapid pressure changes within the fluid. Over time, cavitation can reduce hydraulic performance, increase operating noise, and contribute to premature wear of internal components.
By maintaining proper water filling and stable hydraulic conditions, the HM270-19P delivers reliable pressure performance, efficient operation, and long-term durability across its intended applications.
Impeller And Diffuser
The HM270-19P Horizontal Multistage water pump is equipped with closed impellers securely mounted to the pump shaft to deliver efficient fluid transfer while helping manage the axial forces generated during operation. Featuring enclosed front and rear shrouds, the closed impeller design creates a controlled hydraulic passage that guides water smoothly through the pump, improving efficiency and supporting reliable long-term performance.
Enhanced Hydraulic Performance: The enclosed impeller structure enables water to pass efficiently through the impeller vanes before progressing to the next hydraulic stage or discharge outlet. By reducing turbulence and limiting unnecessary hydraulic losses, the closed impellers help optimise energy transfer, maintain stable pressure generation, and deliver consistent water flow throughout the pumping system.
Closed Impeller Design
Within the volute chamber, the impellers and diffusers are housed within a series of precisely engineered stage bodies. These components, also known as protection brackets, provide structural support while maintaining accurate alignment of the internal hydraulic assembly throughout operation.
By securely locating the impellers and diffusers, the stage bodies help maintain stable pump performance even at high rotational speeds and during continuous operating conditions. This precise internal arrangement allows water to flow smoothly through each hydraulic stage, where pressure is progressively increased to achieve the required discharge performance.
The multi-stage design of the Horizontal Multistage water pump enables efficient pressure boosting across a wide range of applications, from household taps and showers to larger residential, commercial, and water supply systems that require consistent flow and dependable pressure delivery.
Reduced Risk of Cavitation: The closed impeller configuration helps maintain smooth, stable water flow through the hydraulic passages, reducing conditions that may contribute to air entrainment and pressure fluctuations. By promoting consistent fluid movement, the design helps minimise the risk of cavitation-related effects, protecting internal components from excessive vibration, premature wear, and reduced hydraulic performance.
Through precise engineering and integration within the multi-stage hydraulic system, the closed impellers play an important role in enabling the HM270-19P to deliver reliable pressure performance across demanding residential and commercial water applications.
Extended Service Life: By helping balance hydraulic forces and reduce axial thrust during operation, the closed impeller design reduces mechanical stress on critical components such as the pump shaft and bearings. This lower mechanical loading helps minimise wear, reduce maintenance requirements, and improve overall operating reliability.
As a result, the HM270-19P Horizontal Multistage centrifugal pump delivers enhanced durability, extended service life, and dependable performance for continuous water supply applications.
Stainless Steel Material: The impellers and diffusers of the HM270-19P Horizontal Multistage water pump are manufactured from high-quality SS304 stainless steel, providing excellent resistance to corrosion, wear, and continuous water exposure. This durable material selection helps maintain the strength, reliability, and hydraulic performance of the internal components throughout the pump’s service life.
Smooth Surface: Each impeller is precision-finished with a smooth surface to minimise friction losses and reduce turbulence as water moves through the hydraulic stages. By improving fluid flow efficiency and reducing unnecessary hydraulic resistance, the stainless steel impeller design supports consistent pressure delivery while helping optimise energy use during operation.
Excellent Thermal Stability: High-grade stainless steel provides excellent dimensional stability across a wide range of operating temperatures. Whether handling cold or warm clean water, the impellers and diffusers maintain their mechanical strength and structural integrity with minimal thermal expansion or contraction.
This thermal stability allows the HM270-19P to maintain reliable hydraulic performance under varying operating conditions, delivering consistent water pressure and long-term durability for residential, commercial, and light industrial applications.
Generator Defense With Backplate And Mechanical Seal
The backplate and mechanical seal assembly provide essential protection between the hydraulic section and the electric motor of the HM270-19P Horizontal Multistage pump. Positioned between the water-handling chamber and the motor compartment, this assembly creates a separation barrier that helps prevent water from reaching the electrical components. By maintaining this isolation, the risk of electrical damage, short circuits, and premature motor failure is significantly reduced.
To further improve sealing performance, the assembly incorporates a precision-designed sealing system that may include gaskets, sealing washers, and other sealing elements. These components work together to create a secure and leak-resistant connection, preserving the separation between the hydraulic and electrical sections. This robust design supports safe pump operation, enhances reliability, and contributes to the HM270-19P’s long-term service durability.
As the impellers generate centrifugal force to transfer water efficiently toward the discharge outlet, the backplate and mechanical seal assembly continue to maintain a secure separation between the hydraulic chamber and the electric motor compartment. This barrier helps prevent water from entering the motor assembly, protecting the electrical components and supporting safe, reliable pump operation.
In addition to providing sealing protection, the backplate and mechanical seal assembly also contribute to the structural stability of the pump shaft. By helping maintain correct shaft alignment during rotation, these components reduce excessive vibration, minimise shaft movement, and promote smoother mechanical operation.
Through improved component protection and mechanical stability, the backplate and mechanical seal assembly play an important role in enhancing the durability, reliability, and service life of the HM270-19P Horizontal Multistage water pump.
O-Ring And Spacers
O-rings are strategically incorporated throughout the HM270-19P Horizontal Multistage water pump to provide reliable sealing between connected components. By creating secure, leak-resistant interfaces, these seals help prevent water loss within the hydraulic assembly, maintain system integrity, and support efficient, consistent pump operation.
The O-rings are manufactured from EPDM (Ethylene Propylene Diene Monomer) rubber, a material known for its excellent resistance to heat, water exposure, ageing, and environmental conditions. Compared with many conventional elastomer materials, EPDM offers improved durability and long-term stability, making it well suited for applications involving continuous water contact and elevated operating temperatures.
Within the HM270-19P, multiple O-rings are installed at key sealing points throughout the pump, including locations around the volute casing and hydraulic assembly. These seals help maintain effective containment of pressurised water, minimise the potential for leakage, and contribute to the pump’s overall reliability, performance, and extended service life.
O-rings are strategically installed throughout the HM270-19P Horizontal Multistage water pump to provide reliable, leak-resistant sealing between interconnected components. By preventing water loss at internal joints and connection points, these seals help maintain hydraulic integrity, improve operating efficiency, and support consistent pump performance.
Manufactured from EPDM (Ethylene Propylene Diene Monomer) rubber, the O-rings provide excellent resistance to heat, water exposure, ageing, and environmental conditions. Compared with many conventional elastomer materials, EPDM offers enhanced durability and stability, making it suitable for applications involving continuous water contact and elevated operating temperatures.
Within the HM270-19P, multiple O-rings are positioned at critical sealing locations, including areas around the volute casing and hydraulic assembly. This arrangement ensures effective containment of pressurised water, reduces the risk of leakage, and contributes to the pump’s long-term reliability and service life.
Spacers For Stable Operation: Precision spacers are installed between rotating and stationary components within the HM270-19P Horizontal Multistage water pump to maintain accurate clearances throughout the hydraulic assembly. By controlling the spacing between moving components, these parts help prevent unwanted contact, reduce friction, and minimise mechanical wear during operation.
Maintaining correct internal alignment and clearance protects critical components from premature damage while supporting smoother rotation, improved efficiency, and reliable long-term pump performance.
In addition to maintaining proper internal spacing, precision spacers also help reduce vibration by limiting unnecessary movement between rotating components. This enhanced stability reduces mechanical stress, promotes smoother operation, and helps extend the service life of key components, including bearings and other rotating assemblies.
Operating Limits of HM270-19P Water Pump
| Operating Limits | |
| Maximum continuous flow rate | 200L / min (53 US gallons) |
| Maximum operating pressure | 700 kPa* (102 psi) |
| Maximum current | 10 amp |
| Cut-in pressure range | 80% of pump shut-off head |
| Maximum water temperature | 65°C (149°F) |
*Maximum Operating Pressure: The maximum operating pressure of the system may be increased up to 820 kPa, depending on the pressure rating and specifications of the optional pressure tank installed.
*L (Litres): The symbol L represents litres, the standard metric unit used to measure volume.
*kPa (Kilopascal): The kilopascal (kPa) is a metric unit of pressure commonly used in hydraulic, engineering, and water system applications to indicate operating pressure levels.
*psi (Pounds per Square Inch): The psi is an imperial unit of pressure measurement commonly used in pumping and plumbing systems to express water pressure values.
*A (Ampere): The ampere (A) is the standard unit of electrical current, representing the rate of electric charge flow through a circuit. It is commonly abbreviated as amp.
* °C and °F (Temperature Units): Degrees Celsius (°C) and degrees Fahrenheit (°F) are units used to measure temperature. Celsius is the internationally preferred unit, while Fahrenheit is primarily used in the United States.
Hydraulic Performance of Davey's HM270 Horizontal Multistage Pump With Pressure Switch
| Single Phase Models | HM270 |
Motor: P1 kW P2 kW | HM270-19P – P1 kW: 2.4 HM270-19P – P2 kW: 1.9 HM270-25P – P1 kW: 3.2 HM270-25P – P2 kW: 2.5 |
Amps: Run Start | HM270-19P – Run: 10 HM270-19P – Start: 40 HM270-25P – Run: 13.8 HM270-25P – Start: 66 |
Ports (BSP): Suction Discharge | All – Suction: 2 F All Discharge – 1.5 F |
| Nominal operating pressure (kPa) | HM270-19P: 200 HM270-25P: 250 |
| Maximum pump pressure (kPa) | HM270-19P: 300 HM270-25P: 400 |
| Tank air pre-charge (kPa) | HM270-19P: 180 HM270-25P: 230 |
| Nominal flow (L / min) | All in 270 L / min (71 US gallons) |
Electrical Data
| Pump | |
| Speed | 2900 rpm |
Supply voltage
| 230±10% 415±10% |
| Supply frequency | 50 Hz |
Enclosure class
| IP55 IP56 |
| Insulation class | Class F |
*RPM (Revolutions Per Minute): The RPM value represents the rotational speed of the pump motor or shaft, indicating the number of complete revolutions completed in one minute.
*Hz (Hertz): The hertz (Hz) is the standard unit of electrical frequency, representing the number of cycles per second supplied to the motor.
*A (Ampere): The ampere (A) is the standard unit of electrical current, measuring the flow rate of electric charge through an electrical circuit. It is commonly referred to as an amp.
*kW (Kilowatt): The kilowatt (kW) is a unit used to measure electrical power consumption or motor output capacity. One kilowatt is equivalent to 1,000 watts.
Materials of Construction
| Materials of construction | |
| Part | Material |
| Casing | 304 stainless steel |
| Impellers | 304 stainless steel |
| Stages (casing) | 304 stainless steel |
| Pump shaft | 316L stainless steel |
| Stage centring device | 304 stainless steel |
Mechanical seal:
| Carbon Ceramic 316 stainless steel EPDM |
| O-ring | EPDM |
| Plug | 316L stainless steel |
| Motor shell & lantern bracket | Aluminium with baked polyester powder coat finish |
| Motor feet | Xenoy |
| Fan cowl / rear foot (models up to 1.05kW) | Polypropylene |
Horizontal Multistage Pump's Q-H Curve For HM160 & HM270
Included In The Box
Horizontal Multistage Water Pump – HM290-19P
Pressure Switch
User Manual
Proof of Purchase
24 Months of Manufacturer Warranty (Increased by Another 6 Months with e-Warranty Scheme)
Downloads
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