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Tank Takes Long Time To Fill (does not meet claimed GPD)

–    Insufficient water pressure (below 50 psi for non-pump systems) —> Increase house water pressure or add an appropriate pump to system.
–    Low water temperature (below 77 degree F ) —> Increase house water pressure or add pump to compensate for low (cold) water temperature.


Claimed GPD:

The claimed gallon per day (GPD) flow rate for each RO model is rated based on 60 psi input water pressure at 77 degree F water temperature. At this standard water pressure and temperature, the ROES 50 gpd system should make about 1.8 gal of filtered water per hour, the 4-gal tank should fill in 2-3 hours.


Lower water pressure and colder temperature will slow the system’s output to less than the claimed GPD flow rate. Please check your water pressure as the first step in determining the cause of slow flow rate (low GPD).