Nigel Donnelly

See other Advice articles filed in ‘Water systems’ written by Nigel Donnelly
HAVING WORKED IN caravan and motorhome manufacturing businesses for 33 years, I know how much attention is paid by both manufacturers and their suppliers to ensure fresh systems are hygienic when new.

HAVING WORKED IN caravan and motorhome manufacturing businesses for 33 years, I know how much attention is paid by both manufacturers and their suppliers to ensure fresh systems are hygienic when new.


Knowing this though, I was not at all surprised to learn from Jason Paul of APT Innovations, suppliers of the ‘Floë’ water system purging device, that the water that most of us tend to leave standing in pipes and components is not suitable for drinking.


Dirty water from a caravan tapThe Floe system installed on a caravan with an inboard water tank


I confess that my first reaction was “so what”, because I and many others only drink bottled water when caravanning. But then I thought about the trip I recently made to Nepal and how I followed strict advice to use only purified water for teeth cleaning, check that water for tea was thoroughly boiled and avoid salads because they may have been washed in impure water. That’s much more thorough than most people’s caravanning regime. So should water quality be given higher priority or was this just hype to sell more Floë devices?


Is Floë worth the bother?

Floë was designed to prevent damage to taps, pumps etc in the winter when trapped water freezes. It’s a clever but simple device that connects compressed air from a small compressor or footpump, via a choice of adaptors, to the vehicle’s water inlet point. By opening all taps in turn, the escaping air removes all water, which simple draining is unlikely to achieve.


Users of Floë report satisfaction with their purchase but many are surprised by the poor quality of water they see emerging. APT Innovations decided to commission work by the Biomedical Sciences Research Institute at the University of Ulster to establish what was happening. Its findings have recently been reported.


APT told us that in four randomly selected caravans and motorhomes the University found water left standing in pipework, even when the systems had been drained. The experts said that stationary water will deteriorate like this:

After 1 day      Water will lose its Oxygen and absorb Carbon Dioxide
After 7 days    Water will become stale and taste acidic
After 14 days  Water is unfit for human consumption
After 28 days  Water will start to develop bacteria

After 28 days, water shouldn’t be used for washing fresh fruits and vegetables or brushing teeth.


Dirty water from a caravan tapWater containing biofilm purged from the water system by the Floe system


In response to this, water systems would typically be flushed with fresh or sterilised water prior to use after a period in storage. However, the University’s tests showed that this dilutes but does not remove the trapped, stagnant water. So concentrations of bacteria are reduced but they are still present; the stale taste is also likely to be still detectable. 
In contrast, tests on systems purged with the Floë device then re-filled with fresh water showed miniscule or no contamination with bacteria.


The university then examined water recovered from systems that had been purged dry using Floë.  It was found to contain particles of biological film that the compressed air had removed from pipe walls. This film, if left on the pipes would taint water flowing through.
This evidence seems quite convincing.


So, if water hygiene concerns you, it would make sense to invest in a Floë device to keep your water system clean all year round as well as protecting it from winter frost.

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