RO Filter and Membrane Replacement Schedule for Kanpur Homes

What each stage actually does

A typical RO purifier has several stages, and they wear at different rates. Replacing them all together on a fixed date is convenient for the seller but not always necessary for you.

• Sediment filter - removes sand, silt and rust; wears fastest on muddy supply
• Pre-carbon filter - removes chlorine and odour; protects the membrane
• RO membrane - removes dissolved salts; the most expensive component
• Post-carbon filter - polishes taste after purification
• UV lamp - inactivates microorganisms; output falls with hours of use
• UF / alkaline / copper cartridges - optional stages depending on model

Indicative intervals, and what changes them

As a rough guide, sediment and carbon filters are commonly changed within the first year of use, UV lamps roughly annually, and membranes after two to three years. Treat these as starting points, not promises.

In Kanpur, several local conditions shorten these intervals: borewell supply with high hardness, tanker water carrying sediment, an unfiltered overhead tank, long daily usage in a joint family or shop, and long gaps where the unit sits unused.

Signs that beat the calendar

These indicators tell you the true condition of the unit far better than a date on a sticker.

• Output TDS creeping up compared with your earlier readings
• Tank taking noticeably longer to fill than it used to
• Taste or smell changing even briefly after purification
• Visibly discoloured sediment cartridge at inspection
• Reject water increasing without any change in supply

Keeping a simple record

Write the date and the input and output TDS on a small label stuck to the side of the purifier at each service. Over two or three visits this turns into a genuine performance history, and it makes it obvious when a part is actually due rather than merely old.