Water treatment maintenance

Maintenance is what determines whether you get the full 15–20 years HomeGuide reports for a quality softener or half of it. Skipped salt means the resin stops exchanging. Skipped cartridges mean pressure drops and, on a carbon filter, the media stops adsorbing long before it looks dirty. Neither failure announces itself — you just quietly go back to untreated water while assuming you're protected.

The schedule that covers most homes: check the brine tank monthly and refill as needed. Replace sediment and carbon cartridges on the manufacturer's interval — $15–$65 per cartridge. Replace RO pre- and post-filters every 6–12 months at $30–$150 each and the membrane every 2–3 years at $40–$250. Whole-house RO elements are $150–$250. UV lamps are $20–$100 and should be replaced on schedule regardless of whether they still glow; output degrades before the lamp dies.

Service contracts are worth buying when the alternative is not doing the work. At $100–$300+ a year they cost roughly what a couple of DIY cartridge changes do, so you're paying for the reminder and the labor. They are worth avoiding when they lock you into proprietary consumables or auto-renew at a rate that isn't in the original contract. Read the renewal clause.

One honest caveat about "free annual checkups." A no-charge visit from the company that sold you the system is a service call and a sales call at once. It is fine to accept it. It is not fine to buy a five-figure upgrade off the back of a test performed by the person selling the upgrade — get an independent lab result first, the same way you should have at the start.

How to choose

Put filter changes on a calendar, not on memory

A dated label on the housing plus a phone reminder is the whole system. Most premature failures are just missed changes.

Replace UV lamps on schedule

A lamp that still lights can be below its rated output. NSF/ANSI 55 rates systems on performance, which assumes the lamp is within its service life.

Buy salt in the form the manual specifies

Potassium chloride costs meaningfully more per bag than sodium chloride. If you switch, know why you're switching.

Retest annually on a well

EPA recommends annual testing for total coliform bacteria, nitrates, total dissolved solids and pH. Treatment equipment does not remove the need to test.

Question upgrades pitched during a service visit

Take the recommendation in writing, then get an independent test and a competing bid before acting on it.