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Campervans Off Grid

CamperVans / Camping and Off-Grid Water Filtration

Onboard Water / Off-Grid situations

If you’re considering taking your campervan outside of the UK, into Europe and beyond then you need to consider your water situation.

While you’ll probably be able to fill up your onboard water tank with “potable” ie mains-treated water, the quality can vary and you might need to be careful.

Even if you’re using hookups (ie a feed from a local tap) it’s still a good idea to use a filter if the water is from an unknown source (even in an EU country.)

The water might be OK but what about the tap and hoses sitting in that hot sun...

If you're totally Off Grid and want to take “raw water” (aka “Black water”) from a stream, river or lake etc you can put it through a water filter if you know what you're doing.

Important Note: Never drink water directly from a stream or lake. No matter how clean and pure it looks, you won’t be able to see all those tiny micro-organisms swimming around just waiting to get into your body and wreak God knows what havoc....

These are your options:

Option 1: Drinking Water Only / Simple Purification (For Mains-Treated water)

A straightforward “taste and odour” drinking water filter is a great thing to have - so much better than plastic bottled water - and easy and cheap to fit.

This will be suitable if your water source is standard mains-treated water.

But please note this option does not protect you from bacteria / viruses etc that might be lurking in untreated water or dodgy hookup hoses.

You can see our simple water filter for campervans / caravan and boats here.

Option 2: Drinking Water Only / Serious Purification (Non Treated "Raw Water"

To rid your drinking water of potentially dangerous, untreated water, your best option is probably a Reverse Osmosis filter.

(You can read all about Reverse Osmosis here).

Please note: This Option 2 assumes you don’t have a shower in your van and only need a “point of use” drinking water filter. If you do have a shower then go straight to the next section (Option 3) because you will almost certainly ingest water from the shower - without even realising it - and yes it might make you very ill.

Installing a Reverse Osmosis Unit in Your Van

To fit a specially adapted Reverse Osmosis in your RV / Van you need to consider the water pressure. Normally you would already have a pump for the tank and that should do the trick.

(If you are taking water straight from a hook up then pressure is unlikely to be an issue).

The other issue might be the space required for the small but fat Reverse Osmosis vessel

(The RO filters water to an incredibly pure standard but very slowly. So it stores the filtered water in the RO vessel which acts like a buffer tank. Every time you take a drink the tank fills back up with the same amount of water).

The Waste Water Issue

The bad news is that the RO process results in 50% to 70% of the water being rejected / flushed away.

In a standard house where there’s water on tap 24/7 this isn't a problem (the actual waste is only for the RO filtered water ie not all the water used in the property).

But wasting water like this would be an issue if you’re a long way from a refill source.

The solution is to have the rejected-water flow into a separate vessel.

This is easily done - you can simply poke the reject water tube into a jerrycan etc and then top up your main tank with that water.

If you want to re-use the water in this way for your off grid van let us know and we'll consider adapting the drain clamp for this use.

If you want an RO for your van we'll need to customise a couple of things for you anyway - for example to send you the right connection, plus you might want a smaller of larger RO vessel and so on (Contact us to discuss your potential needs).

Option 3: Filtering Your Shower and Drinking Water.

As mentioned above; if you have a shower in your van and are taking water from dodgy or untreated sources then you almost certainly want to filter the shower water aswell because without even realising you will ingest water from the shower.

(When Brits started going to Spain back in the 60s and 70s they wrongly assumed their “Benidorm Belly” was caused by food. In fact it was often caused by shower water and brushing teeth).

To filter shower water - and all the water in your van - you should use an Ultraviolet filter.

You can read all about UVs here.

Putting an UltraViolet Filter in Your Van


The UV unit should always go after the water tank.

(ie never filter water and then store it in a tank. It must be filtered shortly before the point of use or bugs could quickly reappear in it).

Your Power Source

If you have 12V that’s fine. We can provide you with a 12V UV system.

if you have an inverter then you could simply use a standard UV ie on a 3 pin plug for 220V to 240V

But we’ve had feedback that using an inverter drains batteries faster than a 12V.

So, unless you expect regular hook ups to mains power, while the 12V UV is about 20% more expensive than a standard UV it might be worth it?

Flow Rate

UV's are sized depending on how much water passes through them ie the maximum flow rate they will need to handle

You need to consider the flow rate of the water as it moves around around your van.

This will depend on your pump, the size of the pipes and so on.

Do it the scientific way. Get a bucket and stopwatch and time it :)

Then simply give us your a litres per minute calculation and we can give you a quote.

(Here's a guide to finding the flow rate in a property - a very similar process

If you have a UV you won't need an RO

If you use a UV for the whole van then you wont really need an RO - as per Option 2 above - unless you want to play it really safe...

But you might like a “taste and odour “ filter under the kitchen sink for your drinking water. This could make the UV treated water taste sweeter.

Never take “raw water” from a canal

That’s stagnant water, full of poo, hydrocarbons and industrial chemicals.

You'll be asking for trouble.

The only solution is to have several filters - your very own mini-city water treatment plant - that will take up too much space in your van).


Taste and Odour Filters Maintenance (Option 1)

These cost £29 for the whole kit and then £15.95 every 6 months when you change the filter

You should change these regardless of amount used to avoid bacteria build up inside the filter.

Reverse Osmosis Maintenance

You'll need to change 4 filters every 6 months (once they're been "wet" - regardless of the amount of water used).

Our current cost for these is £34 incl UK delivery

You also need to change the mebrane every 3 years or so at a cost of c £79

Ultra Violet Maintenance

You have to change the UV bulb every 12 months regardless of the amount used

The UV (from us) would come with a pre-filter kit. You would need to change the pre filters every 3 to 6 months.You’d know when they need changing because the flow would slow down as the pre-filter gets blocked up.

Important Note about Cartridges

Whichever filter you get make sure it is a universal size one - like the one we sell - which you can change with other brands. There will be nothing worse than being stuck in the middle of nowhere trying to replace a unique cartridge that you’d be hard pressed to find in even a major European city.

At least you have a chance of sourcing the standard / universal size cartridges.


The Taste and Odour and RO Filters come with ¼ inch tubing.

Both kits - if you buy from us - come with their own taps.

You could use this as a separate drinking / cooking water tap on your sink top. They're compact and some clients have used these as their main kitchen tap.

If you have a different tap already fitted and would prefer to use that we might be able to help with adapters - see the parts section here

The UV

The UV pre filter housing has female ¾ inch NPT ports. We usually send these out with 15mm push fit female ports fitted.

We can also supply the pre filter housings for ¼ inch in/out tubing

If you buy from us let us know if you need a different connection and we’ll supply it or help you find it.

The main UV body has ½ inch BSP in/out female threads as standard

Grey Water

Greywater is the term for water that’s been used - particularly in a bath / shower or for washing up. It can also refer to rainwater - if you’re catching that and plan to use it.

You might be thinking about recycling your used grey water.

While this is possible it’s not simple. For starters it would have detergents in it which might also contain a wide range of chemicals

You could use a special filter eg a sand filter (there’s a good article about sand filtering here along with your UV system.

If you filter graywater it would be recommended (although effectively unachievable) to monitor levels of bacteria and toxicological and chemical components that are present in that water.

Filtering the same water over and over would lead to diminishing returns so you would also need a significant amount of top up fresh water into the system pretty often as well.

There simply isn’t an easy, compact system that you could install in a camper van that could handle gray water. While some large US type RV’s claim to have these systems these are for large vehicles and are complex and energy intensive.

If it’s not done perfectly there’s a huge chance of getting ill.

Few companies in the world, including us, would want to put their names on a system like this.

If you’re desperate to do something like this then installing an RO is probably going to get you the closest to what you’re thinking of. It’s just a bad idea though.

On the plus side, if you do manage to do it you’ll have solved a significant part of the world’s water famine issue....

The above information applies to caravans and even boats and yachts.

Drink to your health

Our water filter systems can remove harmful pathogenic bacteria, cysts, parasites, and unhealthy chemical contaminants such as Chlorine, while at the same time leaving in the essential minerals your body needs.


Save money on bottled water purchases by regularly usingfiltered water. Get your highest quality water filters at the best price here.


We supply the widest range of water filters for any needs - residential or commercial.