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Priming a surface pump means filling the casing and the suction line with water before you switch it on, because an impeller can move water but not air. Prime a healthy system once and it holds for months. If yours needs priming every weekend, priming is not really the problem: air is getting into the suction side, or water is draining back out of it, and that is the fault worth chasing.

Which pumps need priming

Anything sitting above the water it draws from needs prime: jet pumps, transfer pumps and most household pressure pumps beside a tank. A submersible sits down in the water and never has the problem, an advantage worth remembering when weighing up submersible against surface pumps. Self priming pumps clear air out of the suction line once the casing is full, but they still need that first fill.

Priming a surface pump, step by step

1. Kill the power at the isolation switch or pull the plug. Do not do any of this with the pump live.
2. Open a tap on the discharge side so trapped air has somewhere to escape as you fill.
3. Unscrew the priming plug on top of the casing. On most domestic pumps it is a brass or plastic cap right above the impeller housing.
4. Pour clean water in slowly until the casing is full to the top of the opening, and if the suction line rises to the pump, keep going until that fills too. A funnel and a bucket beat a hose, because you can see what is happening.
5. Let it settle. The level usually drops as air works out, so top it up until it stops falling.
6. Refit the plug with its washer or o ring seated properly, and do not overtighten a plastic one.
7. Restore power and start the pump with the discharge tap still open. You should get spluttering, then air, then steady water.
8. If it has not pulled water through after a short run, switch off and prime again rather than letting it churn.

Running it dry is what actually kills pumps

The mechanical seal behind the impeller uses the water passing through it for lubrication and cooling. With no water there it is running dry against a spinning shaft, and it does not take a long run to ruin it. A pump that will not take prime should be switched off and diagnosed, not nursed along with repeated starts.

Why the prime keeps disappearing

If you are repriming regularly, one of these is almost always behind it:

• A failed foot valve or non return valve: the most common cause by a mile. That valve holds the water column in place when the pump stops, so let grit hold it open or the rubber seat perish and the line drains back overnight.
• An air leak on the suction side: the inlet line is under vacuum while the pump runs, so a bad joint sucks air in rather than dripping water out. That is why you can walk the line hunting for wet patches and find nothing. Barrel unions, poly fittings and the o ring at the pump inlet are the usual offenders.
• The water level dropping below the strainer: a tank running low or a dam falling away through summer leaves the foot valve gulping air. Sometimes the level is fine but a vortex forms above the strainer and drags air down.
• A blocked or silted strainer: choke the inlet and the pump cavitates, which sounds like gravel rattling through the casing.
• Too much suction lift: every pump has a maximum height it can draw water up, and that figure is on the pump plate or in the manual. Mount it higher, or add a long run of undersized pipe, and it will struggle.

Finding the fault without guessing

The cheapest test is the overnight one. Prime the pump, run it, shut everything down and leave it. In the morning, pull the priming plug. Casing still full means the suction side is sound and you should be looking downstream. Casing empty means water has drained back, which points hard at the foot valve or a leak low in the line.

From there, work up. Pull the foot valve and inspect the seat and the basket rather than assuming it is fine because it looks clean. Redo any suction joints you are unsure of with fresh thread tape or new o rings, because a joint that seals against pressure will not necessarily seal against vacuum. If the pump holds prime until you draw hard on it, suspect the strainer or the water level, not the fittings. Rule out one thing first: a pump starting and stopping in short bursts is a different fault with a similar feel, so read up on a pump cycling on and off before you pull the suction line apart.

Setting the line up so it stops happening

Most repeat priming problems are layout problems. Keep the suction line short, straight and on a continuous rise toward the pump so air cannot pool in a high spot, use the pipe size the manufacturer asks for, keep the joint count down, and sit the foot valve below the lowest water level you expect in a dry spell.

Where the do it yourself part stops

Filling a casing and changing a foot valve are homeowner jobs. Anything involving the pump’s wiring, its terminals or the circuit feeding it is electrical work, and in Australia that must be done by a licensed electrician under your state or territory electrical safety regulator. If the pump ties into your mains or potable supply, or backflow prevention is involved, that side belongs to a licensed plumber under your state plumbing regulator. Drawing from a bore or a watercourse brings its own approvals, so check with your state water authority.

Get the foot valve and the suction joints right and priming becomes something you do once after maintenance, not a weekly ritual with a bucket.

If your pump clicks on and off every few seconds instead of running a steady burst, it is short cycling, and it almost always comes down to one of three things: the pressure tank has lost its air charge, water is escaping somewhere, or the pressure switch has stopped reading properly. None of those fix themselves, and a pump that starts and stops all day will wear out its motor and switch contacts far quicker than one running proper cycles. Here is how to work out which one you have.

What short cycling actually is

A pressure system is meant to work in a rhythm. You open a tap, pressure drops, the switch senses that drop and kicks the pump on. The pump lifts the pressure back up until the switch senses the upper limit and shuts it off. That cycle should take a decent stretch, not a heartbeat.

Short cycling is when the rhythm collapses and the pump runs for a second or two, stops, then starts again straight away. You will hear it before you see it: a rapid tick, tick, tick from the pump shed or the side of the house, sometimes with the taps pulsing. The pump is cramming a full day of starting work into a few minutes, and motor starts are the hardest thing a pump ever does.

The pressure tank is the usual suspect

Most pressure systems have a small tank beside the pump, and inside it is a rubber bladder with a cushion of air on one side. That air stores the pressure so the pump can rest between draws. Lose the air and there is nothing left to store it in, so the pump switches on the instant you crack a tap and off again the moment you close it.

Two things go wrong here. The air charge slowly leaks away over the years, which is normal and rechargeable. Or the bladder splits, which is not rechargeable and means a new tank. To tell them apart on a small tank, press the air valve on top with the system switched off and depressurised. A puff of air suggests a charge problem you can top up. Water coming out of the air valve means the bladder has failed.

Do not go hunting for a magic pressure number online. Every tank has its own correct pre-charge, set relative to the pump’s cut-in point. Use the plate on your tank and the pump manufacturer’s instructions, not something you read on a forum.

Leaks bleeding pressure while nothing is running

If the tank checks out, suspect water going somewhere it should not. A healthy system sits still for hours with everything closed. If your pump fires up in the middle of the night with no tap open, something is leaking. Common places to look:

• Toilet cisterns: a worn flush valve trickles quietly and is the most common cause of a pump kicking on overnight.
• Outside taps and garden fittings: a slow weep at a hose fitting or a cracked poly joint will do it.
• The foot valve or non-return valve: if it fails, water drains back down the suction line and the pump loses prime between cycles.
• Buried irrigation lines: a split under mulch or lawn loses plenty without ever showing on the surface.

The simple test is isolation. Shut the valve between the pump and the house and watch the gauge. If pressure holds while the house is isolated but falls once you open it back up, the problem is downstream in the plumbing. If it falls either way, look at the pump, the tank and the non-return valve.

A pressure switch or controller on the way out

The switch tells the pump when to start and stop, and it lives a hard life. Contacts pit and burn over time, and the small sensing port that reads water pressure can silt up or corrode until the switch is reading a fraction of what is really happening. Either fault gives the same symptom: a pump starting and stopping on a hair trigger. Electronic controllers fail their own way, with a sticking flow sensor or a scaled up sensing chamber convincing the unit you are still drawing water when you are not.

Diagnosing a switch properly means working around live terminals, and that is where the job stops being a homeowner one.

What you can safely check yourself

With the pump switched off at the isolation point, you can watch the gauge over an hour to see whether the system holds, walk the property listening for leaks, drop food colouring in each toilet cistern to see whether it seeps into the bowl, look for damp patches around fittings, and read the plate on your tank and pump. Recharging a pressure tank with a bicycle or compressor pump is within reach for a lot of people, but only once the system is isolated and fully depressurised, and only to the figure on the plate.

When to stop and call a licensed trade

Anything involving the pump’s wiring, its terminals, the pressure switch contacts or the supply circuit is electrical work, and in Australia electrical work must be carried out by a licensed electrician. That is not a guideline, it is the law in every state and territory, enforced by the relevant electrical safety regulator. Opening a switch cover to poke at contacts on a live pump is the kind of shortcut that kills people. Leave it and make the call.

If the fix touches your mains connection, potable supply or backflow prevention, that is a licensed plumber’s job under your state plumbing regulator. Garden irrigation on the outlet side is generally fair game, but the moment work joins the drinking water system it needs a plumber.

The good news is that most short cycling comes back to a flat pressure tank or a leaking toilet, and both are cheap to sort. Chase those two first and you will fix most cases before anyone touches a wire.

On a rural block or a big bush property, a bore can be the difference between hauling water in a tank on the ute and just turning on a tap. But the hole itself does nothing without a pump, and the pump is where most of the head scratching happens. Choose the wrong one and you either burn it out chasing water that sits too deep, or pay for grunt you will never use. Here is how bore and well pumps work, and how to pick the right one.

When a bore or well pump makes sense

Bore water suits properties where mains supply is either not connected or too dear for the big jobs: filling stock troughs, running irrigation across a few acres, or keeping a house going off tank and bore together. If you only need a bit of extra garden water, a rainwater tank and a small pressure pump is usually the cheaper path. A bore earns its keep once your demand is steady and high enough that a reliable underground source beats carting or metered town water. The trade-off is the commitment: you need a driller to put the hole down, a pump matched to that hole, and in most states an approval before anyone drills.

Submersible bore pumps versus surface jet pumps

There are two broad families of pump for a bore, and which one suits comes down mostly to how far below the surface the water sits.

• Submersible bore pumps: the whole unit drops down inside the bore casing and sits under the water, pushing it up the pipe from below. Because they push rather than suck, they handle deep water a surface pump cannot reach, and they run quietly down the hole.
• Surface jet pumps: these sit up top in a shed and draw water up through a suction line. They are easier to service and cheaper to start with, but they can only pull water up so far before the physics beats them. Once the water sits beyond the reach of suction, a surface pump is the wrong tool.

As a rough rule, shallow water leans towards a surface pump and deep water needs a submersible. But do not guess it off a blog: size it against your actual bore, which brings us to the numbers that matter.

Why bore depth and water level drive the choice

The most important thing about your bore is not how deep the hole is, it is where the water sits and how far that level drops once you start pumping. When a pump runs, the water falls to what drillers call the drawdown level, and the pump has to lift from there, not from the resting level. A decent bore report or driller’s log gives you the standing level, the drawdown and the yield, and those are the figures a supplier uses to match a pump to your hole. Never let anyone size a pump without them, and never just copy a neighbour’s setup, because two bores a paddock apart can behave completely differently.

Water quality, sediment and filtration

Bore water is not automatically clean water. Depending on your area it can carry sand and silt, run high in iron that stains everything a rusty orange, or sit at a pH that slowly chews through fittings. None of that stops you using it for stock or garden, but a water test early on saves you buying the wrong gear:

• Sediment: grit wears pumps out and blocks drippers, so a sand separator or sediment filter is common on grittier bores.
• Iron and minerals: these cause staining and scale that a specialist should sort.
• Drinking water: bore water is not safe to drink until it has been tested and, where needed, treated. Treatment and health rules are matters for your state health or water authority, not something to eyeball.

Bore licensing and groundwater rules

This is the part people skip and then regret. In Australia, drilling a bore and taking groundwater is regulated by each state and territory, and the rules genuinely differ from one border to the next. Depending on where you are, you may need a licensed driller, a works approval before drilling, and a licence to take water, with limits on how much you can pull and what you can use it for. So the only right answer is to check with your state or territory water authority before you drill. Do not take a rule you read online, this guide included, as the final word for your own patch.

Who installs and connects it

A bore pump job touches two licensed trades.

• Electrical: any bore pump beyond a plug-in portable needs its power supply wired in on an outdoor rated circuit protected by a safety switch. That wiring is a licensed electrician’s job.
• Plumbing: the moment bore water is connected into your house plumbing, or anywhere near your drinking water supply, you are into licensed plumbing territory, including the backflow prevention that keeps the two supplies from crossing. A licensed plumber such as CS Plumbing Services handles that connection so the bore feeds the house safely and to code.

Typically the driller puts the hole down and often drops the pump, the electrician powers it, and the plumber ties it into the house. Keep those roles clear and you avoid the classic bore headache: a pump that runs beautifully but is wired or plumbed in a way that fails an inspection.

The short version

A bore is a great long-term water source for the right property, but the pump makes or breaks it. Match it to your bore’s real water level and drawdown rather than the total depth, go submersible for deep water and surface only for shallow, test before you treat, and sort the licensing and the licensed trades first. For how this fits alongside tanks and ponds, see our guide to water in the Australian garden, and for pump types more broadly, our explainer on submersible versus surface pumps.

If your pool pump is the single biggest power user in the house, you are not imagining it. The pump is what keeps a pool clean and safe to swim in, so how you size it and how you run it makes a real difference to both water clarity and your electricity bill. The good news is that getting it right is mostly about matching the pump to your pool and running it smartly, not chasing the most powerful unit on the shelf.

What the pump actually does

A pool pump is the heart of the filtration circuit. It pulls water from the skimmer and the main drain, pushes it through the filter to strip out dirt and debris, sends it past the chlorinator or dosing gear, and returns clean water to the pool. Nothing else in the system works without that flow. If the pump is undersized or clogged, the filter can’t do its job and the water goes cloudy or green. If it is wildly oversized, you are just burning power, and you can even push water through the filter faster than it can properly clean.

Single-speed versus variable-speed pumps

There are two broad types you will come across:

• Single-speed pumps: they run flat out whenever they are switched on, at one fixed speed. Cheaper to buy and simple, but they draw the same power whether you need full flow or not.
• Variable-speed pumps: you can dial the speed up or down to suit the task, running slow and quiet for everyday filtering and faster only when you are vacuuming or backwashing.

Most of a pool’s daily filtering doesn’t need full flow. That is the whole case for a variable-speed pump, and it is why they have become the default recommendation for new installs.

Why variable-speed usually costs less to run

The savings come down to how pumps use energy. Running a pump slower uses a good deal less power than running it flat out, so a variable-speed unit ticking over gently for most of the day draws far less than a single-speed pump hammering away at full noise. Across a whole filtering season that difference adds up. I won’t put a dollar figure on it, because it depends on your pool, your tariff and your hours, but the pattern is consistent: slower and longer beats fast and short for everyday filtering.

Matching the pump to your pool

The goal is turnover, meaning you filter roughly the whole pool volume over a set period so the water stays clean. A bigger pool, or one with plenty of swimmers and leaf litter, needs more turnover than a small, sheltered plunge pool. Rather than guessing, work from your actual pool volume and the filter you already have, and let a pool shop or installer match a pump to it. Bigger is not better here. An oversized pump costs more to buy, more to run, and can strain an undersized filter. A right-sized pump quietly does the job for less.

Running times and off-peak

You don’t have to run a pool pump around the clock. The aim is enough total turnover across the day, and you have some freedom in when that happens. Two habits help:

• Split the run: a couple of shorter cycles, timed around when the pool actually gets used, often keep the water clearer than one long block.
• Lean on off-peak: if you are on a time-of-use tariff, shifting filtering to cheaper off-peak hours trims the cost without cutting the turnover.

Warmer months and heavy use call for more running time. Through winter, when the pool is barely touched, you can usually wind it right back. A timer, or a variable-speed pump’s built-in schedule, makes this close to set-and-forget.

Repair or replace an ageing pump

Pumps don’t last forever. A screeching motor, a pump that keeps losing prime, leaking seals, or a unit that trips the power are all signs something is on the way out. A worn seal or a blocked impeller is often a straightforward fix. But if you are nursing an old single-speed pump through repair after repair, swapping it for a modern variable-speed unit often pays for itself in running-cost savings before long. When you do replace it, remember one hard rule: the electrical connection of the pump is a licensed electrician’s job, not a DIY exercise for any hard-wired unit. And because pool areas carry their own safety and fencing requirements that vary by state, check your local requirements rather than assuming.

Get the sizing right, run it on a sensible schedule, and a pool pump becomes the quiet, efficient workhorse it is meant to be.

Every time a decent storm rolls through, the water pools against the back slab and starts creeping toward the door. You bail it, you sweep it out, and the next downpour it is right back. That is the exact job a sump or stormwater pump is built for: shifting water that has nowhere else to go, before it gets inside. Here is how they work, how to tell a pump problem from a plain drainage problem, and who should be doing the connecting.

What a sump or stormwater pump actually does

A sump pump sits in a pit at the lowest point of a space that keeps flooding: a garage, a laundry, a shed floor or a boggy yard corner. Water drains into that pit, the pump senses it, and it lifts the water up and out to somewhere it can drain away safely. A stormwater pump does the same job on a bigger scale, clearing the runoff a heavy storm dumps faster than your normal drains can carry it off. Both are usually submersible units that sit down in the water rather than perched above it, and our submersible vs surface pumps guide covers that style versus a surface pump. Worth saying too: not every drop has to be pumped to waste, the clean roof runoff is often worth catching in a tank, which our rainwater harvesting guide covers, but a sump is about the water that has already pooled where you do not want it.

The pit, the float switch and how it runs itself

The clever part of a sump setup is that it looks after itself. You are not meant to stand there flicking it on. Three bits do the work.

• The pit: a lined hole at the low point that gathers the water and gives the pump a reservoir to draw from, so it is not chasing a thin film across the floor.
• The float switch: a floating trigger that rises with the water and kicks the pump on at a set level, then drops and shuts it off once the pit is drained, so it only runs when there is actually water to move.
• The discharge line: the pipe that carries the water up and away to a legal discharge point, kept clear and running downhill so nothing flows back into the pit.

Get those three right and the system quietly does its thing through a wet week without you thinking about it.

Pump problem or drainage problem? Work out which first

Before you spend a cent on a pump, be honest about why the water is turning up. A pump treats the symptom, but sometimes the water should never have pooled there at all. Have a look at the lie of the land after rain. If the ground slopes back toward the house, or a paved area sheds to one low spot, the real fix might be regrading, a spoon drain or a strip drain to carry water away before it ever collects. A pump earns its place where water genuinely has nowhere else to go, a below-grade garage or a natural low point, not as a patch over drainage that could be sorted properly. Money spent getting the fall right often saves you running a pump for the life of the house.

When a blocked stormwater line is the real culprit

Here is the one that catches people out. The pit keeps filling, the pump keeps straining, and everyone blames the pump, when the actual trouble is downstream. A stormwater line choked with tree roots, silt or a collapsed section cannot take the water away, so it backs up and floods the very spot you are trying to keep dry. If a pump that always coped suddenly cannot keep up, or water is surfacing at pits and gullies it never used to, suspect the line before you condemn the pump. Clearing or repairing that pipe often fixes the flooding outright. One important note: where stormwater is legally allowed to discharge, whether to the street, a legal point of discharge or the kerb, varies by council, so check your local requirements rather than just running a pipe to wherever is handy.

Backup for the storm that really matters

The cruel irony of a stormwater pump is that the storm big enough to need it is often the one that knocks the power out. A mains pump with no electricity is just a lump of plastic in a full pit. If flooding into the house is a genuine risk, it is worth a backup: a battery-backed pump that carries on when the power drops, or a second pump plumbed in so one can take over if the other fails. On a property that floods badly it is cheap insurance against the worst night of the year.

Who installs and connects what

This is where you draw a firm line. Dropping a portable pump into a pit and running a hose for a one-off is one thing. A permanent sump or stormwater system is another, and parts of it are not DIY.

• The electrical side: connecting a pump to power, or putting a proper outdoor point where one is needed, is work for a licensed electrician on an RCD-protected circuit, not something to wire up yourself around water.
• The pit and discharge: cutting a sump into a habitable or below-ground floor, and where the water is legally allowed to go, is not straightforward, and discharge points can be regulated by your council, so it pays to get it designed and signed off properly.

Sort out why the water is really there, get the pump matched to the job and the drainage done right, and leave the wiring and the fixed discharge to the licensed trades. Do that and the next big storm becomes a non-event instead of a night bailing. For how this sits alongside the rest of your outdoor water setup, our guide to water in the Australian garden ties it all together.

The quickest way to choose between a submersible and a surface pump is to ask where the water is. A submersible pump sits down in the water — in a tank, pond, sump or bore — and pushes from below. A surface pump sits up on dry ground and draws water up to itself. Each suits different jobs, and the limiting factor for surface pumps is how far they can suck water upward. Here’s how to match the type to your task.

The two broad pump families

Almost every water pump falls into one of two camps based on where it lives. Submersible pumps are built to be fully underwater and they push water up and out. Surface pumps stay dry, sit beside or above the water source, and pull water up before pushing it on. That single difference — pushing from in the water versus pulling from above it — drives most of the practical trade-offs in noise, access, priming and what each is good at.

Submersible pumps: where they shine

Because they sit in the water, submersibles are excellent wherever the water is contained or below ground: emptying or pressurising tanks, circulating ponds, clearing water from sumps and pits, and drawing from bores where the water is well below the surface. Being underwater makes them quiet — the water muffles the motor — and they’re self-cooled and never need priming, since they’re always surrounded by the water they move. The trade-off is access: to inspect or service one you have to lift it out of the tank or pit.

Surface and self-priming pumps: where they shine

Surface pumps stay on dry land, which makes them easy to reach, check and maintain. They suit drawing from shallow sources — a tank where the water sits near or above the pump, a shallow well, a stream — and transferring water from place to place. Self-priming versions can clear air from their suction line and get themselves going, which is handy where the pump sits above the water. The catch is that they have to lift water up to themselves before they can push it on, and there’s a limit to how far up they can pull.

Suction lift and priming — the limit people forget

This is the single thing that catches people out. A surface pump can only pull water up so far before it simply can’t lift any more — that vertical distance is its suction lift, and physics caps it. The exact workable distance depends on the pump, the pipework and your conditions, so don’t treat any single figure as a universal rule. If your water source sits well below where the pump would go, a surface pump may struggle or refuse to prime, and a submersible — which pushes rather than pulls — is usually the better answer. When in doubt, check the suction lift against your actual setup before buying.

Noise, access and maintenance differences

Submersibles are quiet because the water absorbs the sound, but they’re out of sight and a little more effort to pull up for a look. Surface pumps are easy to inspect and service since they’re right there in the open, but they’re more audible — worth considering if the pump sits near a patio or bedroom window. Think about how often you’ll need to get at the pump, and how much noise you can live with, alongside the technical fit.

Matching the type to the job

Put it together by source: tanks can go either way depending on where the water sits; ponds and sumps lean submersible; bores with deep water almost always want a submersible; shallow draws and general water transfer suit a surface or self-priming pump. Get the family right first, then size the pump to the work.

Two rules apply to both types. The electrical connection must be done by a licensed electrician on an outdoor, RCD-protected circuit — especially important with submersibles sitting in water. And any connection to mains or potable water, including backflow prevention, is licensed plumber’s work. Position and plumb the garden side yourself; bring in the trades for those connections.

Choosing a pump type is one piece of the wider water picture — see how it fits with tanks, ponds and efficient watering in our guide to water in the Australian garden.