[sham33]

Hi, would one of these work ok on tap pressure alone? or would some sort of pump be needed?. I want to stick one in the back of the van and top up when i can at customers property as i work.

I would probably put the ro water strait into the tank and use a di vessel to polish the water before it goes through the pole.

Thanks

[AJ]

Tap pressure is fine where I am. I have no idea what the pressure is, but its fine for my membrane.
They are sold as a low pressure membrane.

[sham33]

N1, how many litres an hour do you think you get with tap pressure? and whats the tds of the water before and after RO if you dont mind me asking  

[Spruce]

Hi Sham
Fellow window cleaner has a 4040 from Pure Freedom. We have water pressure of 60 psi with a tds of around 100 ppm. He has an H4 membrane and the system is unpumped. He told P/F that he fills his 1000 litre tank in around 6 hours.

He didn't know his tds after the r/o but hasn't changed resin in his di vessel yet. The Di vessel is the one supplied by P/F which holds 6.5 litres of resin. His system is 18 months old.

I think you have to tread very carefully when 'topping up' at a customers house, even if they offered you water. There is also the problem of the waste - if a customer sees this, even if he agreed to you filling up, I think you will be on a collision course with him, especially if he is on a meter. Ideally, an r/o needs to run as it takes a while for the membranes to settle down and the tds to drop. Stop start water purification will cost more in membranes and resin.

Spruce