[Paul Golding]

Hi.

I am hoping to build my own system, but would like suggestions on Ro units.

What differences are there between
http://www.gapswater.co.uk/acatalog/Reverse_osmosis_kits.html

and a smaller one, ie.

http://www.ro-man.com/shop/product_info.php/cPath/22/products_id/150

I am looking to work with a maximum of 400ltrs a day, but I'm looking at overall cost . . Ie. I will need to polish it off with a DI but don't want to be spending tons on resin. I live in a hard water area.

Is it best to spend more innitially for a good unit or does it not make much difference, if that being the case I might aswell go for the cheap small one ??

Thanks

[Alex Gardiner]

The main question you need to decide is 'are you going to process your water at home into a static tank and then into your vehicle tank or will you want to process it all in your vehicle?'

If you want to process at home into a static tank then the 300gpd will be the most economical (set-up and maintenance) way to achieve this. It will produce on reasonable pressure about 700-900 litres per 24hr day. More than enough for your needs, especially if you have a 1000 litre static holding tank you will always have some in reserve.

If you need to process in your vehicle, then as long as your are on good water pressure you could just manage on a 300gpd in the vehicle processing overnight (12 hrs = about 400 litres). However the '4040' type system would guarantee a delivery of about 100-200 litres per hour depending on water pressure but would need more careful maintenance.

The 300gpd will probably give you better TDS output than the 4040 hence saving on your Resin costs but it will waste more water in doing so, not so good if you are on a water meter.

Alex Gardiner

[Extremeclean]

If speed of water production isnt a real issue.  IE you dont want to top up as you go the small membrane type of units are probably your best bet. They are far cheaper to buy, less expensive and hassle to maintain and very good at reducing TDS so saving money on resin.

I have both types and each have their place I think. I have a 300 GPD pumped unit I got from Andrew McCann at pure freedom for £195 delivered. It gives me around 8 to 900 ltrs per 24 hrs. TDS in is 420 ish and out its 8 or 9. Waste ratio is less than 1 to 1. I run it into an IBC as Alex says but it could run directly into a van tank as well. It would fill the 400 no problem overnight I think but I always like the buffer of water an IBC gives you just in case.

I,ve also dealt with Gapswater in the past and find them very well priced with products and service 2nd to none.

Rich.