[Inskip1991]

Thinking about getting a cheap backpack kit to reach awkward windows, con roofs etc which cannot be done trad.

One question though, how do you fill them so the water is pure?

What I don't understand is if you just pour the water into the backpack tank, how does the filter have chance to purify it? Might be a simple answer but I cannot think! 

Any help appreciated.

[Window Washers]

Thinking about getting a cheap backpack kit to reach awkward windows, con roofs etc which cannot be done trad.

One question though, how do you fill them so the water is pure?

What I don't understand is if you just pour the water into the backpack tank, how does the filter have chance to purify it? Might be a simple answer but I cannot think! 

Any help appreciated.

you need a water treatment system (it makes purified water) like and OR and DI, backpack is just a delivery system (it just pumps water)

[William McCafferty]

You fill a holding tank with pure water, you then transfer into 25l containers and use these to fill backpack

[Inskip1991]

Ok thanks for the replies, so basically you need a static tank in a garage or warehouse for example, which makes the pure water, you then just transfer that into the backpack?

[simonr]

depends on your tap water if its a  low ppm you only need a di vessel & some 25ltr cannisters. you need to buy a tds meter , about £15 , from w/cleaning suppliers to test it , if your water has a high ppm then its a bit more complicated

[Tom White]

Ok thanks for the replies, so basically you need a static tank in a garage or warehouse for example, which makes the pure water, you then just transfer that into the backpack?

If it's just for the odd few windows a water butt would suffice.  Leaves and stuff may find their way in there, but it won't affect the water purity, oddly enough.