12 Volt Caravan Water Pumps, Filters & Accumulators

What kind of caravan water pumps do we sell? 

We offer several choices for 12v caravan water pumps that is more than enough power for medium and large vans. We highly recommend doing your research on what kind of electrical system you want in your RV before purchasing, but if you're decking out a bus or a truck, you’ll want to go for a 24v pump from Seaflo or Flojet to match the starter batteries current.  

As with any electrical device it is necessary to have an appropriately sized fuse close to the battery on the positive wire. The current draw on a 12v water pump is quite low, so a smaller gauge electrical wire around 2.5mm to 4mm will do the trick. We recommend running a twin core cable from the battery positive and negative terminal to your 12v water pump rather than ‘earthing’ to the chassis, as earthing to the chassis may cause issues with your system. If you do not want to use a 12v system in your RV at all, we offer a caravan hand pump, foot pump or ‘sink’ pump for a manual water system. Check out our wide range from Camec for the best options.   

Understanding flow rates: 

A caravan water pump will produce a certain flow rate and depending on where it is placed in the van this will effect its maximum output and its ability to perform. The standard measurement for flow rate is set as litres per minute. There is a big difference in flow rate depending on your needs. Most stock caravans will use the Shurflo 4009 12v water pump which can run several appliances at once. If you are living out of the back of a 4x4 then you will only need a Shurflo Compact 12v water pump which is only about 4 litres per minute, which helps to conserve water. 

So, a simple way to understand what this is imagine you are trying to fill a 10-litre bucket in 1 minute. A water pump like the Shurflo 4009 with a flow rate of 12 litres per minute will fill that bucket in 50 seconds. This kind of flow rate will allow someone to use the sink whilst someone is in the shower and should not affect the water pressure in either. A flow rate of 4 litres per minute will be unsatisfactory for a shower in a caravan but is more than enough just for filling water bottles in a smaller 4x4 set up. In summary, less is more when travelling light. We highly recommend the Shurflo compact 12v pump for smaller rigs.  

Under pressure: 

Water pressure is measured as PSI or bar. 

PSI = pounds per square inch. Bar can be calculated at 14.5psi = 1 bar. When the pump reaches the cut-off pressure it will stop pumping. 

Cheaper caravan water pumps like the Whale Inline 12 volt pump or any of the submersibles have to be hard wired to a switch for them to work. Whereas an automatic caravan water pump like the Shurflo 12v 4009 does not draw any current whilst appliances are not in use. An automatic pump will turn off when water pressure in the line reaches a certain level. Most high quality 12v water pumps have a pressure sensor built in and will start to pump when the pressure inside the outlet pipe is less than the cut-off pressure (Shurflo 4009 = anything under 45psi). Put simply, when the tap is shut off water builds up in the line because there is nowhere for it to go. When the tap is open, the build-up of water pressure is released creating a flow rate. The water pump continues to run until a certain PSI is reached when the tap is shut off and will then automatically stop.  

Some caravan and motorhome appliances are not compatible with the mains pressure of caravan parks which can be up to 80 PSI. A pressure limiting device such as the Shurflo inline water regulator which can be installed just after the mains inlet is recommended where a hot water system is installed. The only permanent hot water system in our range that requires this is a TRUMA hot water system. If you are looking to use something more portable like the Bushranger instant hot water system for example, these higher quality instant hot water systems, will come with an inbuilt pressure regulator making them compatible with most mains water outlets. However, it is important to check before ordering any of your appliances to see if they are compatible with your water pump. The Bushranger kit comes with a compact 12v pump rated at 4.5Lpm, but you can use something like the Shurflo 4009. Even though this water pump is rated for a higher PSI, this will not make a difference to the shower pressure and will not damage this appliance because of its inbuilt water regulator. The seals in cheaper hot water systems may wear out faster over time if it’s used in conjunction with the wrong water pump or under mains pressure.  

Popular hot water systems such as the Suburban do not require an inline or permanent mains water regulator. Another key thing to remember when installing your plumping is that flow rate and pressure can be affected by the diameter and lengths of the pipes. Meaning that depending on how far away your appliances are from the pump or how thick your caravan hose pipes are (12mm or 1/2 inch recommended) the output of the water pump will perform at its best when placed according to the recommended height and distance from you water tanks and appliances.  

What does it mean when my caravan water pump cycles? 

Very simply, when the caravan water pump turns on and off this = 1 cycle. The more cycles a water pump does the harder it has to work to do its job, meaning it will heat up faster.  This is an important factor to remember when wanting to get the most longevity out of your water pump. For instance, if you are in the shower and trying to conserve water by turning the tap off and on quite frequently this will cause the water pump to work harder. Conserving water is important when traveling in a motorhome, as it can become inconvenient to have to fill up all the time. Some people are happy to shower in this way, but if you wanted to conserve the same amount of water by only turning your tap on halfway you would need to install an accumulator to compensate for the pressure build up in the line.  

If you do not install an accumulator and your pump is rated at 10 litres per minute and you are only trying to use 5 litres, this will cause cycling as the pump needs to turn off until the pressure reduces in the water line. This will cause what is called rapid cycling and will significantly shorten the life span of your 12v water pump.   

An accumulator will keep the water pressure consistent no matter how far you have the tap on. It means less noise, less amperage draw, and reduced water pulsation. It also mitigates the effect of the pump and the benefits of this is that your appliances will flow like the ones at home. 

Any excess water pressure being created from the water pump that can't escape, will be held in the accumulator. When it’s full, the pump will stop and the water will still flow from the tap until the accumulator is empty. This step will repeat itself until the appliance is not in use, essentially giving you a full range of pressure options at a steady rate.  

Most of the newer water pumps on the market like the Shurflo 4009 have in-built bypass technology which eliminates the need for an accumulator. This means that when the pressure increases, some of the water goes back into the tank to be used later. But if you're looking to upgrade your current system, the Shurflo accumulator tanks are a great addition to any RV.   

Filters and Installation: 

Adding a filter is strongly recommended to prevent dirt and other debris entering your pump and causing damage to the internal structure or diaphragm. That is why it’s important to place a water filter BEFORE the pump as any damage caused by this is not covered by warranty. Filters are also easier to access for cleaning and cartridge replacement on the inlet side because no water will be held in this side when the pump is disconnected and turned off. One of our best-selling water filters for motorhomes are the B.E.S.T caravan inline water filters which use micron technology. It is recommended that this filter works best with a water pump that has a pressure rating of about 8-10L per minute. 

Many of the pumps in our range will suck up water from the tank to the height of about 1.8m. This is called a ‘self-priming’ water pump. However, it is important to understand the dry prime height as placing and installing your water pump will likely depend on the layout of your motorhome and if you are converting a bus that can be up to 7 metres long, you must consider a few factors.  A water pump that can pump air and water or ‘run dry’ without damage will make life much easier. A small amount of our cheaper water pumps will wear out faster and will be less likely to retain water in the inlet side, meaning they need to ‘prime’ by sucking air first in order to pump water. The solution to this is either replacement or renewing the internal diaphragm, so we recommend a self-priming 12v water pump placed within 1.8m of each water tank for the best long-term results.  

Secure the pump to a solid support wall that won’t rattle or vibrate. A good quality pump should be relatively quiet but will operate even quieter when fixed to a solid surface. Adding sound deadening to the surrounding areas will also dramatically reduce vibration. Each pump requires a different installation, so it’s best to double check the manual before permanently fixing.  

By installing your 12v pump in a more accessible area in case the water pump filter needs to be cleaned or the actual pump needs parts replaced, this will save you a lot of hassle. The area should be well vented, dust/dirt free and away from objects that may cause damage to it when driving. Using a non-rigid, flexible water hose or pipe that is free standing from surfaces is the best location to reduce vibration and excess noise near the pump.  

Hoses and pipe fittings: 

Food grade caravan water hose is usually 25mm from the water tanks to the 12v water pump inlet. After that we recommend food grade John Guest 12-13mm water hose. You can use PVC piping or regular plastic hose, but you will need to add a water filter if you plan on drinking from it.  All appliances such as a 12v water pump, instant gas hot water systems and filters have a pressure rating and depending on whether you are using soft or hard hose, the water pressure is likely to change. It will only be a slight difference but the 12mm John Guest drinking water hose is manufactured so that it maximises the water pressure in line. If you want to get the most out of your 12v water pump and a steady pressure rating, choose appliances and a filter that are all rated at roughly the same water pressure. For example, you can use a B.E.S.T caravan inline water filter which is traditionally meant for larger motorhomes, in a compact 4x4 set up but the pressure would be slightly lower because it must pass through a caravan water filter that is rated at 6l pm and if you are using PVC hose piping that is slightly softer it will again affect the water pressure as it has slightly more give in the material.  

It’s good practice to use slightly bigger piping before the inlet of the 12v water pump to help maximise the water flow rate. Each individual pump will tell you what hose fittings or water pipe that will work best for you, but if you are looking for something more unique feel free to give us a call and our expert customer service team will help you find what you're looking for.  

Keep in mind every set up is different, if you are unsure about any of the information above and would like more clarification before purchasing, please give our friendly customer service team a call.  

Why shop with Outback Equipment? 

• We’re Australian owned and operated – We’re based right here in the south of Brisbane. If you ever need help with an order or a product, you can call straight through to our friendly local team. 

• Plenty of payment options – You can pay via PayPal, MasterCard, Visa, zipMoney, Afterpay, and direct deposit – whichever is most convenient for you. 

• Delivered to your door – You don’t have to worry about darting across town to grab your order. We deliver your goods straight to your door to save you time and energy. 

Order Your 12v Caravan Water Pump Or Filters Today 

Stay in complete control of your plumbing with our range of caravan 12v water pumps and water filters. For the best 12v water pumps Australia has to offer, shop online to find the finishing touches for your recreational vehicle today.