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AO Smith Maintenance

AO Smith Water Heater Maintenance — Annual Checklist

The annual maintenance schedule that doubles AO Smith water heater lifespan. Coregard anode, Hydrojet sediment management, T&P testing.

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Updated May 2026 · AO Smith Water Heaters

AO Smith water heaters live 10–14 years with no maintenance and 16–20+ years with the right annual care. The difference is dollars and downtime.

Annual maintenance — every year

1. Flush the tank

Sediment accumulates in every tank water heater. AO Smith's Hydrojet system on Signature Premier helps reduce buildup but doesn't eliminate the need for annual flush. Procedure:

  1. Shut off power or gas
  2. Shut off cold inlet
  3. Open hot faucet to break vacuum
  4. Attach garden hose to drain valve
  5. Drain to flush sediment (full empty in hard-water areas; 2–3 gallon partial elsewhere)
  6. Close drain, restore inlet, refill while hot faucet runs
  7. Restore power/gas AFTER tank is full

2. Test T&P relief valve

Flip lever fully open for 1–2 seconds. Water rushes out; should stop within seconds when released. Dribbles after release = replace valve (~$25, 30-min DIY).

3. Inspect for leaks

Visual check around tank base, connections, T&P discharge.

4. Burner chamber inspection (gas only)

Open access door. Look for spider webs (vacuum), rust, weak pilot flame (clean orifice).

Every 3 years

Inspect the Coregard anode

AO Smith's Coregard anode (aluminum-zinc alloy) depletes 2–3x slower than standard magnesium anodes. Pull and inspect:

  • Original full diameter, steel core wire encased = good, reinstall
  • 50–75% consumed = note for next inspection
  • More than 75% consumed = replace

See our Coregard anode page.

Year 5 milestones

  • Replace anode rod — even if Coregard still looks OK, year 5 replacement typically doubles tank lifespan
  • Replace T&P valve — preventive
  • Upgrade drain valve from plastic to brass if not already done
  • Check elements (electric)

Voltex hybrid-specific maintenance

  • Clean air filter every 3 months — front-panel filter; clogged filter reduces efficiency
  • Compressor coil clean every 2 years — vacuum the fins
  • Condensate drain inspection every 6 months
  • Anode check year 4, replace year 6

ProLine Tankless maintenance

  • Annual descaling required to maintain warranty — 60–90 minutes with descaling pump kit
  • Inlet filter clean monthly first year, annually thereafter
  • Vent termination clean annually

Bottom line

Annual flush + anode at year 5 + T&P at year 5 + brass drain valve = ~$80 in parts and a 50-100% lifespan extension. The math is unambiguous. For specific parts see our AO Smith parts directory.