RO Filter change

[trevor peacock]

How often should you change the pre filters and membrane?

Do they look dirty, are there any indicators?

I've looked around and there are a lot of different opinions, any advice appreciated.

 

[Trev81]

I got told 3 months for pre filters, I reckon they could prob go a bit longer, depends on how much your pure your producing and your tap TDS.

R/O should be good for a few years if the tap pressure is good and the pre filters are maintained.

 

[peter rogers]

it is meant to go on how much water u put through them andthe tds blah blah blah but prefilters are cheap as chips and easy to replace every few months the ro 4040 membrane i flush nightly now and i havent even looked to change it in 4 years as water still comin out below 010ppm

 

[doug atkinson]

A key indication that you filters need changing is when your pressure gauge drops you then know your filters are clogged.

Plenty of filters on the market but always ask for the specification as this will give you an idea how litres the filter can treat.

In some cases you may get more or less but totally depends what is in your water.

Due to this heavy rain people are changing their sediment filters a bit more regular as there is more sediment in the water at the moment.

Cheaper doesn't mean better value for money as if you worked out the cost per litre in the long run the well know brands like Pentair give you better value for your money.

 

[Green Pro Clean Ltd]

@doug atkinson you talk of the 'pressure gauge' where does this fit in in line with the system?

 

[doug atkinson]

In between the filters and membrane http://www.daqua.co.uk/images/hoverimg/rosystem2.jpg

 

[spruce]

I have 2 gauges, one before the sediment and one after the carbon block. I can see when the sediment needs changing when the gauges are reading different pressures by a margin. I also have them in clear housings so I can also see the the muck on the sediment filter.

A carbon block lasts me 3 months but I often have to replace the sediment filter every month.

 

[Gray]

With my R/O from purefreedom, they said pre filters every 3 months and membranes every 12-18months

 

[steve garwood]

I personally change the pre filters every 4 months and the membranes every 2 years

 

[Green Pro Clean Ltd]

Ok and is there a guide as to what the pressure guage reading should be?

 

[spruce]

For me our tap water pressure is 50psi. Both gauges are identical and were bought at the same time. (That doesn't guarantee they will register the exact same pressure under the same conditions though, but they should be pretty close.)

Even when the filters are new the second gauge reads fractionally less. When the second gauge gets to around 40psi I change the sediment filter. It is usually pretty red by then but hasn't got to the slimmy stage if you know what I mean.

I just watch the progress of the dirt on the sediment filter and decided that this pressure difference worked for me. There was no instructions that I followed.

 

[Gray]

Is it true that at this time of year because the water temp is lower the R/O has to work harder and the water pressure drops giving u a higher ppm before DI??

 

[Gray]

Plus the pre filters are not due to be replaced and the membranes are only 10 months old, my unit is a 450gpd purefreedom. The ppm once flushed is between 20-22

 

[Gray]

Plus the pre filters are not due to be replaced and the membranes are only 10 months old, my unit is a 450gpd purefreedom. The ppm once flushed is between 20-22

Oh and our pressure seems really high but don't have a gauge.

 

[spruce]

Is it true that at this time of year because the water temp is lower the R/O has to work harder and the water pressure drops giving u a higher ppm before DI??

Cold water has a different viscosity to warm water. Ice is a solid. As the tap water gets colder production will get slower. Not sure about ppm with cold water. My 4040 produces the same tds in both summer and winter. (I have an inline tds meter sensor on the r/o output before the di and then another sensor after di.)