low pressure on ro

[canadawest]

Hey Victor,

My RO unit has about 55psi of pressure going through it when the sediment and carbon filters are new. As they get clogged up the pressure drops. I usually replace both when the pressure drops below 30psi (about every 4-6 months for me).

I find when I buy the 1 micron filters I have to change them more often (every 3-4 months) than when I buy the 5-10 micron filters (4-6 months average life). So as a compromise I buy the 1 micron sediment filters as they are really cheap, and a 5 or 10 micron carbon block filter as it's the carbon filter that seems to affect the pressure more so than the sediment filter when clogged up.

This combination tends to give me around 6 months useful life before the pressure drops too low (clogged up) and peace of mind that I'm changing the carbon filter frequently enough to avoid chlorine damage to the expensive RO membrane. The other train of thought is that the 1 micron sediment filter should pick up most of the particulate before it even gets to the 5 or 10 micron carbon block filter, thus the carbon filter allows better flow for a longer period of time before getting clogged up.

Also to extend the life of my cartridges and reduce sediment I run my cold water line for 30 secs before running it through the RO/DI unit. This way most sediment (or whatever) is flushed through before getting into the unit.

Just my $0.02 worth.