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Water Water - but not everywhere

At home we don't need to think much about utilities like water - it's all there quite literally 'on tap'.  In our motorhomes things are rather different since we need a clean, portable and reliable water supply and while you can have a ‘water hook-up' on some super pitches this may not always be possible or indeed very convenient.   

Fresh Tanks:  The simplest answer of course is to use a container to collect water from a nearby tap as caravanners do.  In practice this means having another container as well to take the waste water but these are not very convenient in a motorcaravan where you are frequently on the move - even if just for days out.  In practice then almost all modern motorhomes of any size will have both fresh tanks as permanent fixtures and many will have waste tanks too.  Our own smallish coachbuilt has a 120 litre (26 gallon) fresh water tank under one of the dinette seats and a 100 litre ‘grey waste’ tank under the kitchen floor.  The tanks are kept dark either in a cupboard or by being made from black polythene to help prevent algae growth.  The filler is usually outside with a locking cap - and a clear symbol for water, to discourage anyone from filling up the water tank with fuel - but this is not unknown - nb!!

There are a few ‘if, buts and maybes’ to think about here.  How will you keep the water clean, fresh and drinkable?  How much will you need / how long will it last?  What about weight?  What about freezing in winter?  All impossible questions of course but let’s try to get some idea of what’s involved. 

The ‘clean and fresh’ requirement is not too difficult if you use your motorhome frequently.  Each site will have standpipes for drinking water even remote farm sites have them - usually in the field but sometimes at the farm.  At home we prepare for a trip by flushing out the tank with a couple of mini-fills of our chlorine-laden home tap water, flush through the taps, then fill the tank right up and use the water just as we would at home, including delivering all drinking and cooking water through a decent in-line filter.  An occasional clean out with something stronger is a good idea but don’t use bleach and the like because it will taint the tank.  Milton is an old and reliable favourite well known to parents in much of the world.  Estimating water usage is more difficult - our German 120 litre tank is often described in UK reviews as ‘generous’ but as rather ‘mean’ in France - perhaps they shower more than us?!  In practice we’ve found that the 120 litres will last two holidaying people somewhere between 2-4 days without any noticeable hardship.  Many motorhomes now have tank gauges so that you can monitor your supply albeit in rather vague amounts like and full.  Designers often put the fresh water tank amidships so that the 120 Kgs of added weight is between the axles and maintains the balance of the vehicle.  Some owners prefer to travel with an empty tank but this can be very inconvenient - and hopeless if you wild camp - and we've never noticed any real penalty as a result of running with everything full and ready for use.

Winter Do you want to use the motorcaravan in winter?.  If so then ideally you should buy a ‘van that has its fresh water tank and all its plumbing contained within the heated interior.  This is rather more difficult in smaller campervans where space is at a premium.  An additional plus of an inboard tank is that you can get at it easily for cleaning.  Many have an access port fitted on top with a large screw cap which allows one to both look in and to reach into the tank.  External tanks and pipe-work runs can he protected against freezing by insulation, although that alone only delays the onset of ice formation.  Again individual life style comes into play - if you intend to camp in seriously sub-zero temperatures and will be out on the piste for hours then you need to fit a thermostatically controlled immersion heater in the tank(s).  There are units which operate on both 12 volts and mains power.  If on the other hand you mostly stay in the warm and admire the view through your double glazed windows then the heat that keeps you warm will often keep the water from freezing too. 

Another possibility for the winter months is to carry or install a supplementary water container inside your motorhome. Some folks do this anyway to carry a limited supply of drinking water that doesn’t go via the main tank.  Consideration must then be given to storing this full container while on the move!  If you don’t want to use the ‘van at all in Winter then you must drain down all water at the end of the season according to the makers instructions, remembering to include the hot and waste tanks and all taps, pipes and showers. Leaving taps and drains open helps to keep the tanks fresh but do remember to use some gauze or mesh to keep out unwanted wildlife!

Tank Filling:  It’s not immediately obvious but you should use only food-grade hoses and containers. Ordinary garden hose and watering cans may be made of plastics which can give water an unpleasant taint that is difficult to eradicate once in the system. Food grade plastics are often colour coded blue but all items bought from caravan accessory shops are normally OK. 

On many sites you can get a motorcaravan close enough to a tap for fill-up - but don’t count on it, especially if there are caravanners on site some of whom just love to park right in front of the tap.  Don’t count on there being a hose provided either. This can actually be a good thing for hygiene reasons; many site owners make it the responsibility of the user to ensure a clean hose is used, you just wouldn’t believe what some people do with water hoses!!  So carry a length of say 3-6 metres, fitted with a universal tap connector to cope with any eventuality.  We also carry a couple of rolls of lay-flat hose for emergencies, they are a bit inconvenient in use (especially draining them after use) but they don’t take up much space and can be daisy chained together when really needed; one deep-frozen night in northern Germany readily springs to mind!   The Whale version comes with an excellent adaptor set too.

If you can't get near enough to the supply point, or don't want to move your motorhome, you'll need a container - and of course somewhere to store it. Then you will need some means of getting it into the tank and this will depend on whether it is light enough to lift or not.  A convenient sized tube will be needed to go into the filler tube which is often about 3" in diameter usually with a near horizontal entry so allow for a 6" or more insertion to avoid run-back.  If you don't want to or can't hoist the container off the ground then you can use a small submersible pump to transfer water to the ‘van tank and then you'll need both a 12v supply and a second 'breather' tube as part of the assembly.  A few motorhomes come equipped with a filler unit incorporating a 12V socket and plug-in for a dedicated hose/pump assembly, some of which can be combined with inlet filters and all this can be retro-fitted at some cost.  A similar kit could be used to deliver water from containers kept inside for occasional winter use.  By the way, the containers you buy might be food-grade but they probably won't be light-tight so don't leave water standing in them for too long or you'll start to see green algae growing on the sides - sometimes in just a day or so in summer. 

It would be nice, of course, if one could just plug in to mains water as one does to mains electricity. That has long been possible on many sites in North America - where you may be able also to connect directly to drains and TV and telephone services as well.  Such facilities are now starting to appear on some of the more developed sites in Britain.  Best known is the so-called 'Superpitch' system; their pitch service unit supplies water at the reduced 1 bar pressure required by motorhome water systems and water heaters in particular. It is possible to hook up to outlets at normal mains pressures providing your connecting system includes a suitable pressure reducer. Kits are made by Munster Simms Engineering - branded Whale, Carver, and Superpitch themselves. 

Pumps and Taps:  In a domestic system ‘mains pressure’ forces water to taps and showers so that water flows if you simply open the tap.  In a motorcaravan a pump is needed to supply pressure and naturally enough you must be able to start and stop the pump as required.  Manual pumps are rarely seen these days so we will talk only about electric pumps.  There are two popular methods of control - tap based ‘micro-switches’ and in-line pressure switches.  In the first system tiny devices built into every tap switch the pump on as the tap is opened and off as it is closed.  This works quite well but does add to the complexity of the motorcaravan wiring and tends to give rather erratic performance when two or more taps are opened together.  Also the micro-switches used are sensitive to damp and can fail when water tracks across their contacts.  The second system of pressure switching seems to be becoming more common since it mimics home use rather more closely.  An automatic switch in the water system runs the pump until about 1 bar / 15 psi is generated and then switches off.  Opening a tap allows water to flow out under pressure and the inevitable pressure drop causes the pump to switch on again.  The whole process is ideally smoothed using small pressure accumulators or ‘dampers’ but these are sometimes omitted to save on cost.  They can be retro-fitted fairly economically and multiple units can be installed to improve performance.

Because there’s a potential for flood with any pressurised system a separate pump isolator switch should be fitted - usually near the motorcaravan main control panel.  It’s advisable to switch the pump off when leaving the ‘van or when going to bed.  Pump technicalities are not of great interest to most of us but pumps described as ‘self-priming’ are the best choice because they can pump air temporarily, after a drain-down for instance.  Alternatively if the unit is made with the motor fully enclosed so as to be waterproof then it can be immersed in the water tank and avoid the need for priming. Such pumps are simple, consequently quite cheap, and reasonably reliable.  ‘Diaphragm pumps' are generally preferred since both high flow and high pressure can be achieved, more outlets can be served and performance is notably superior when it comes to showering but they are bulkier and more expensive.  All water systems need simple filters to keep out dirt and grit and these should be cleaned from time to time - perhaps annually.

Water Filters:  Many people like to use filtered water for drinking. This can be done in a motorhome by fitting an inline filter into the water system.  Some units like the one from Whale are throwaway whilst others like Carver and Jabsco use a renewable cartridge.  Most improve taste and remove numerous harmful chemicals, some like the ‘Nature Pure’ from General Ecology remove pathogens too.  Their literature demonstrates removal of giardia, cryptoporidia, viruses, pathogenic bacteria, pesticides, solvents and chlorine plus foul tastes and odours.  While the better products are hardly pocket money purchases, most of these filters are not unduly expensive and must be regarded as excellent value for the performance given.  More adventurous travellers wouldn’t be without one. 

Choice of the position of the filter depends upon whether you want to treat water to the kitchen tap only, to all cold water outlets or to the whole hot/cold system.  Most people opt for kitchen-cold-only to maximise cartridge life and then installation itself is usually quite simple.  The popular budget units employ a silverised cartridge with ion exchange resin and activated carbon. By mechanical action they can reduce particulate matter and algae while the silver content destroys many bacteria and the absorption processes take out chlorine, toxic metals and substances which cause taste and odour problems.  Manufacturers' recommendations about filter life vary but in any case cartridges should be changed annually.

Maintenance Water left in a tank can, of course, become stale and therefore unpleasant. How often you drain the tank to avoid staleness will depend upon the frequency with which you use your motorhome, the resultant throughput of water and the quality of the local water. We give our tank a mini flush out every time we start a trip and always run the taps on the second part-fill to flush out the stale water in the pipes.  You may need to drain down your whole system in winter to avoid freezing and an annual flush-through and clean is good practice at the start of the 'season' even if you have continued motorcaravanning through the colder months. 

Water heaters and pumps are particularly prone to frost damage and expensive to repair or replace. Some of the latest storage-type heaters now come with a thermostatic valve which drops the water when the temperature nears freezing and an owner has forgotten to act - but don't just rely on that.  Instant water heaters, with narrow passageways through their heat exchangers and no insulation, will be first to freeze and to split when the thaw comes.  You do need to familiarise yourself with the manufacturer’s instructions for winter draining of the units in your ‘van.  Usually this involves opening all taps and all drain cocks but that may not be enough to completely empty the system.  Blowing back down the taps and taking the vehicle for a drive in the 'open' condition will encourage pipes to empty themselves.  There may be additional vents and drains that are opened with a coin or screwdriver - check the instructions!  Purists will also disconnect pipes at pumps and flick them on for a few seconds to expel any retained water.  Others who want to use the motorcaravan all year round may simply heat the motorhome during the winter months - as we do.

For that annual flush-through you can buy special cleaners at accessory shops or 'Milton' at some supermarkets or many chemists and baby shops - even at motorcaravanning shows. Milton Sterilising Fluid is a highly effective anti-bacterial solution which is also non-toxic. It is easy to use and will ensure your drinking water, and storage containers, are free from bacterial contamination.  Flush through with water and then fill the system with a solution of Milton at a rate of 30ml to every 5 litres of water.  Make sure that this reaches the taps and shower head by letting the water flow until you can smell the Milton. (Take care not to get the solution on your clothes because it can bleach). Leave for at least 30 minutes, or overnight if the system has not been used for a long time, then flush through thoroughly.  Note: if a water filter is fitted the cartridge should be removed from the system during the cleaning procedures and a new one fitted after final flushing.

Water heating ... Coming soon 

With thanks to Motorhome Monthly for permission to use one of their articles as inspiration for this one (www.stoneleisure.com).


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