Surface Pumps

A surface pump is any pump that sits above or alongside the water it is moving, rather than being submerged in it. The pump has a visible inlet and outlet, and pipes connect it to the water source on one side and the delivery point on the other.

Most small drainage and flood pumps are submersible: you drop them in and they pump the water out from below. Surface pumps work differently. They need to be protected from the weather, positioned within reach of the water source, and in many cases they need to draw water up to themselves before they can start delivering.

The main advantage of a surface pump is accessibility. If anything fails or needs servicing, you do not need to lift a heavy pump out of a wet hole. The pump is right there, dry, on a shelf or a mounting plate.

When to Choose a Surface Pump

Use a surface pump when the water source is a tank, a swimming pool, a pond, a stream, or any source that can be piped to the pump, when you need continuous running, when you need to boost the pressure of water that is already flowing, when you are running sprinklers, irrigation systems or fire-fighting equipment, or when the application involves a fluid that needs a specific material specification such as seawater or oil and a suitable surface pump can be specified.

Use a submersible pump instead when you are pumping out a flooded basement, sump, cellar, or hole. Use submersible when you need to drain water from a confined space where a surface pump cannot sit above, when you need portability for emergency or hire use, or when the application is intermittent drainage rather than continuous transfer.

The Five Jobs a Surface Pump Does

Every pump in this range does one of five jobs. Identifying which job you need is the fastest way to narrow the range.

1. Transfer Pumps

The pump sits at water level or slightly below, with the inlet flooded by the water source. The job is to move water from where it is to where you want it. Flow rate matters more than pressure.

Typical uses: moving water from a holding tank to a delivery point, food processing wash-down lines, light industrial cooling, general water circulation where the source is above the pump.

Pumps in this category: Speroni C(M), CF(M), WX(M)-A, GA(M)100.

2. Self-Priming Pumps

The pump sits above the water source. Before it can deliver, it has to draw water up through a suction pipe and clear the air out of the line. Once primed, it runs normally.

Typical uses: drawing water from a below-ground tank, pumping from a stream or pond where the bank is higher than the water, pumping from a rainwater cistern, garden and allotment watering where the water source is below pump level.

The critical spec is maximum suction lift, usually 7 or 8 metres. If the water is further below than that, no self-priming pump will work and you need a submersible or borehole pump instead.

Pumps in this category: Speroni CA(M) cast iron and stainless jet pumps, RA(M) self-priming multistage, AKM60 peripheral.

3. Pressure Booster Pumps

Water is already available. The job is to deliver it at higher pressure. Multistage pumps achieve this by stacking impellers in series: each stage adds pressure without adding flow. This is why booster pumps can be smaller than transfer pumps but produce much more head.

Typical uses: sprinkler and irrigation systems, fire booster systems, industrial washing and process water pressurisation, cooling system circulation in commercial and industrial buildings, multi-storey buildings fed from a stored water tank (not direct from mains), pressurisation of rainwater harvesting systems, long pipe runs where friction loss reduces pressure, horticultural and agricultural pressurisation.

Pumps in this category: Speroni RS(M), RV(M), RSX(M)2, RSX(M)4, RSX(M)10, 2C(M), CMX, CTX.

Note: these pumps are not WRAS approved and are not for mains drinking water supply.

4. Pool Circulation Pumps

Pool pumps do a specific job that transfer pumps cannot do as well: they run continuously, they handle chlorinated or salted water, and they incorporate a strainer basket to catch debris before it reaches the impeller. Pool plumbing uses specific connection sizes and the pumps are designed for 24-hour duty during season.

Typical uses: domestic swimming pool filtration, commercial and leisure pool circulation, above-ground pool systems, saltwater pool systems.

Pumps in this category: Plastica iFlo (small pools), Plastica AG (above ground), Plastica Argonaut AV (commercial and saltwater), Speroni SWIMM (all-round domestic and commercial).

5. Specialist Fluid Pumps

The fluid being pumped is not clean fresh water, so material choice becomes the main decision.

Seawater can be pumped by the Speroni KS1100/PA, built with plastic body and 316 stainless shaft to resist chloride corrosion, for marine, coastal, and harbour applications.

Oils and lubricants use the Viscomat, a rotary vane pump designed for transferring engine oils, gear oils, and lubricants up to SAE 140. Not for water, fuel, or solvents.

Light chemicals and food-grade use the Speroni WX(M)-A with open impellers, stainless construction, and hard-faced seals for food processing, washdown, and 25% glycol solutions.

Domestic auto-start and rainwater applications are covered by the FL Water Demand Pump and Umbra Pompe Acuasystem, built around specific domestic use cases rather than general transfer.

Understanding the Speroni Naming

The Speroni range dominates this collection. The naming looks cryptic but follows a consistent logic once you know it.

• An M at the end of the model name (CM, RSM, RVM, CAM) means 230V single-phase.
• No M means 400V three-phase.
• C prefixes the single-stage centrifugal range (C, CF, CM, CMX, CTX).
• R prefixes the multistage booster range (RS horizontal, RV vertical, RSX stainless, RA self-priming multistage).
• 2C is a twin-stage centrifugal.
• CA is a self-priming jet pump.
• K prefixes the peripheral range (KF, KP, KS, AKM), smaller low-flow high-head pumps for boosting and boiler feed.
• GA is an open-impeller single-stage for slightly dirty water.
• WX is an open-impeller stainless for food and chemicals.
• Anything with an X in the model name (RSX, CMX, CTX) has stainless construction on the wet parts.

How to Choose the Right Surface Pump

Start with the job: transfer, self-prime, boost, pool, or specialist. Once you know the job, the range narrows immediately.

The next questions are what the water source is and where the pump sits relative to it. If the pump is below or at water level, any transfer pump works. If the pump is above, you need self-priming and you need to check the suction lift spec.

After that, what flow rate you need (in litres per minute), what pressure you need to develop (in metres of head), whether the supply is 230V single-phase or 400V three-phase, and how clean the water is.

Getting Help

If this is a replacement for an existing pump, take the make and model from the label on the old pump and send it to us. We will match like-for-like. If the old pump failed early, it may have been undersized; send us the details of your installation and we can help size up correctly.

If this is a new installation, send us the suction lift, the delivery height, the pipe run length, the flow you need, and the water source.

Important Notice for Mains Drinking Water

The Speroni range is not WRAS approved. This means these pumps are not certified for use on mains drinking water in the UK. They are designed for irrigation, sprinklers, fire systems, cooling loops, industrial and agricultural water, pool and pond circulation, rainwater harvesting, and other non-potable water applications.