How to Choose the Right Type of High Pressure Pump and Avoid Costly Mistakes


Putting the wrong pump on a water blaster, jetter or high pressure pump system will cost you time, money and machine life. Not to mention the fact it’ll probably under perform and have you swearing under your breath from the moment you install it to the moment you have it replaced or worse your machine dies.  

Every machine, every industry is different and it is important to select the right pump to maximise your efficiency and get the best return on your investment.

There are many different types of high pressure pumps, each designed with a unique purpose or situation in mind. Choosing the right type of pump is the first and most important step in the process, then you can move onto calculating items like pressure and flow and selecting the right model from within that pump style to suit your specs.

Key features you should keep in mind when choosing a high pressure pump are the rating, size and conditions of your work. Before purchasing your pump check that it is designed to work with the flow, pressure, inlet conditions, temperature, duty cycle and liquid compatibility of your job. Also do some research on its longevity, parts availability in New Zealand and the typical length of intervals between required servicing.

Don't make the mistake of fitting an undersized pump onto a machine to try and cut costs. Operating your pump outside of its rated performance will reduce its efficiency, flow and general lifespan, costing you more money in the long run.

To help you make the right choice we’ve broken the most common high pressure pumps into categories and outlined their unique features and ideal applications.

Plunger Pumps (Direct Flow)
Plunger pumps are better suited to high pressures of up to 483 bar (7000 psi) and are highly versatile with optional manifolds of forged brass, nickel aluminium bronze and 316 stainless steel. Plunger pumps put out significantly greater pressure than piston pumps. These high pressure pumps are available in a variety of drive options including belt drive, direct drive, gearbox and standard belt drive.

Piston Pumps (Uniflow)
Piston pumps are typically better suited to applications requiring medium pressures of up to 103 bar (1500 psi) or when a suction inlet is necessary. Piston pumps have a lower risk of cavitation, provided the pump is properly primed, their only downfall is that they tolerate less pressure than plunger pumps. Due to their relatively low RPM’s (typically under 800 RPM) piston pumps are generally intended for belt drive installations.

Gearbox Pumps
Gearbox pumps are designed for heavy duty, portable, petrol engine, pressure washers as they offer a simple, compact and direct mount to a petrol engine. The gearbox is attached directly to a variety of plunger pumps eliminating the selection, installation and adjustment of pulleys and belts.

SF – DX Pumps (Super Flow)
SF pumps offer a more economical direct drive option than the gearbox pumps. In theory SF pumps are a combination of both piston and plunger pump designs making them extremely high quality. They are ideal for misting and portable pressure washers intended for commercial, intermittent use.

Nickel Aluminium Bronze (NAB) Pumps
Nickel Aluminium Bronze pumps are constructed with a special manifold material requested by the reverse osmosis market. Several sizes are available rated from 3.8 – 265 L/MIN (1 – 70 GPM), 7 – 345 bar (100 – 5000 psi) with belt drive, gearbox, direct drive or complete power unit options.

316 Stainless Steel Plunger Pumps
316 Stainless Steel Plunger Pumps are designed for the harsh continuous-duty reverse osmosis installations, sanitizing and ag-chem applications. Their unique 316 stainless steel block head construction makes them extremely dependable. These pumps are rated from 3.8 – 265 L/MIN (1 – 70 GPM), 7 – 483 bar (100 – 7000 psi) and have special viton and EPDM elastomer options. They are also available in belt drive, gearbox, direct drive or complete Power Unit options.

Flush Pump Manifolds
Flush pumps are used for low lubricity liquids (de-ionized water) and liquids with elevated temperatures. They feature a ported inlet manifold that permits an external flush liquid to circulate between the low- and high-pressure seals. This system helps to extend seal life when pumping liquids with special characteristics. Other benefits include the containment of pumped liquids, a safer work environment and reduced maintenance.Flush pumps are available in brass and 316 stainless steel, and in performance ranges of 2 – 227 l/min (0.5 – 60 GPM) and 7 - 483 bar (100 – 7000 PSI).

Specialist High and Ultra High
High pressure water jetting pumps and positive displacement plunger pumps for process pumping are available for ultra high pressure work of up to 3000 bar (43,500 psi). Water jetting applications include surface preparation, sub-sea cleaning and hydro demolition. Process pumping applications include umbilical testing, well testing and glycol injection.

Kerrick services and supplies some of the world’s best known high pressure pumps. Our range includes high pressure pumps from CAT pumpsHawkInterpump and Pratissoli as well as ultra high and specialist pumps from Hughes Pumps and Gardner Denver.

Your local Kerrick team has a long history of working with high pressure pumps in New Zealand and can help you work through your options to find the best pump for the job. Our engineering knowledge and design build capabilities are backed up by quality products and the experience of our international suppliers, so you can rest assured you’ll be in good hands.

To talk to specialist call Kerrick on 0800 253 774 or send an enquiry through our website, our friendly team will get back to you quick smart! Kerrick’s range of pumps covers the following applications:



Pressure cleaning

Surface preparation

Salt water injecting

Hydro demolition

Wet sandblasting

Abrasive cutting (cold cutting)

Hydrostatic testing

Heat exchange cleaning

Reverse osmosis

Compressing gas / Well testing

Dust suppression


Misting / spraying

Food processing

Vehicle washing

Sub-sea cleaning

Boiler feed

Railway cleaning

Machine to coolant

Pipeline and Flowline testing

Chemical injection

Methanol injection / Glycol injection

« Back