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Plumbing & Water · Fixtures & Equipment
Water Heater
One of the three most failure-prone systems in any home — and one of the most ignored. Most water heaters give clear warning signs for 1–2 years before they fail. The homeowners who catch them save $800–$3,000 in emergency replacement and water damage costs.
All 9 zonesLifespan: 8–20 yrs depending on typeFound in 99% of homesPlumbing & Water
Avg replacement cost
$900–$2,400
installed, depending on type
Emergency vs. planned
+$400–$800
premium for unplanned failure
Most common failure
Sediment / anode
preventable with annual flush
DIY-able tasks
~70%
of routine maintenance
Select your type
Gas tank water heater — the most common type in the US. Brands include Rheem, AO Smith, Bradford White, and State. Lifespan typically 8–12 years. The two tasks that extend life most: annual sediment flushing and anode rod replacement every 3–5 years.
Maintenance tasks
| Task | Cadence | Skill | Time | Consequence if skipped |
|---|---|---|---|---|
Flush sediment from tank Connect hose to drain valve, flush until water runs clear | Annually | 2 · Confident | 30 min | Sediment insulates the burner — efficiency drops, unit works harder, lifespan cut 2–4 years. Rumbling noise is the warning sign. |
Inspect / replace anode rod Sacrificial magnesium or aluminum rod that prevents tank corrosion | Every 3–5 yrs | 2 · Confident | 45 min | When the anode is depleted, the tank itself corrodes. Rust-colored water is the late warning. Tank failure follows within 1–2 years. |
Test TPR valve Lift the lever briefly — water should flow, then stop cleanly | Annually | 2 · Confident | 5 min | A seized TPR valve is a safety hazard — overpressure has no release. This is the most skipped and most critical safety test. |
Inspect flue / exhaust vent Check for rust, separation at joints, proper slope away from unit | Annually | 2 · Confident | 10 min | Backdrafting flue means combustion gases — including CO — enter the home instead of exhausting outside. |
Check temperature setting Should be 120°F — dial on gas valve | Annually | 1 · Beginner | 2 min | Above 140°F: scalding risk + accelerated sediment. Below 110°F: Legionella bacteria growth risk. |
Inspect supply and discharge lines Check flex connectors and shutoff valve for corrosion or weeping | Annually | 1 · Beginner | 5 min | Corroded flex connectors can fail suddenly — significant water damage. |
Gas line and connection check Brush soapy water on fittings — bubbles indicate a leak | Annually | 2 · Confident | 5 min | Gas leak. If you smell gas at any time, leave immediately and call the gas company. |
Thermocouple replacement Pilot won't stay lit — thermocouple has failed | Every 8–10 yrs or as needed | 3 · Advanced | 1 hr | No hot water. Most common reason a pilot light won't stay lit. |
Troubleshooting
Symptom
Likely cause
Action
Who
No hot water / pilot won't stay lit
Failed thermocouple
Replace thermocouple — $15 part. Relight per label first.
DIY ok
Rumbling during heating
Sediment buildup
Flush sediment immediately. Persistent noise after flushing = near end of life.
DIY ok
Rust-colored or smelly water
Depleted anode rod
Replace anode immediately. Rust after replacement = replace unit.
DIY ok
Water pooling at base
TPR discharge, drain valve leak, or tank failure
Identify source. Tank seam leak = replace unit immediately.
Call pro
Hot water runs out faster than usual
Sediment displacing volume, or dip tube failure
Flush first. If continues, check dip tube (pre-1997 units common failure).
DIY ok
Gas smell near unit
Gas leak
Leave home immediately. Call gas company from outside. Do not use any switches.
Evacuate
Recommended tools & materials
Recommended tools & materials
Electric tank water heater — two heating elements (upper and lower). No flue, no combustion. Same sediment and anode rod maintenance as gas. Lifespan typically 10–15 years. Element failure is the most common service call and is very DIY-friendly.
Maintenance tasks
| Task | Cadence | Skill | Time | Consequence if skipped |
|---|---|---|---|---|
Flush sediment from tank Same process as gas — drain valve, hose, flush until clear | Annually | 2 · Confident | 30 min | Sediment covers the lower element causing it to overheat and burn out. Most electric WH element failures are sediment-related. |
Inspect / replace anode rod Sacrificial rod protects tank from corrosion | Every 3–5 yrs | 2 · Confident | 45 min | Tank corrodes from the inside once anode is depleted. Electric tanks often outlive gas units — only if the anode is maintained. |
Test TPR valve Lift lever briefly — water flows then stops cleanly | Annually | 2 · Confident | 5 min | Safety valve failure — same overpressure risk as gas. |
Test heating elements Multimeter continuity test — no continuity means burned out | Every 5 yrs or if slow heat | 3 · Advanced | 30 min | Failed lower = lukewarm water. Failed upper = no hot water. Elements are a $20 part — early detection saves a service call. |
Check thermostat settings Behind access panels — upper and lower should both be 120°F | Annually | 2 · Confident | 10 min | Mismatched thermostats cause short cycling, poor recovery rate, and element burnout. |
Inspect 240V circuit breaker Check for tripped breaker — double-pole in panel | Annually | 1 · Beginner | 2 min | A repeatedly tripping breaker signals an element short — ignoring it risks panel damage. |
Recommended tools & materials
Tankless gas water heater — brands include Navien, Rinnai, Noritz, Rheem, Bosch. Lifespan 20+ years when maintained. The heat exchanger scale is the enemy. In hard water areas, descaling is the single most important annual task.
Maintenance tasks
| Task | Cadence | Skill | Time | Consequence if skipped |
|---|---|---|---|---|
Descale / flush heat exchanger Circulate white vinegar or descaler using a pump kit | Annually (6 mo in hard water) | 2 · Confident | 1 hr | Scale reduces efficiency 20–30% and eventually cracks the heat exchanger — a $500–$1,200 repair. Most common tankless failure. |
Clean inlet water filter screen Screen at cold water inlet — remove, rinse, reinstall | Annually | 1 · Beginner | 10 min | Restricted flow causes low-flow shutoff errors and uneven heating. |
Inspect venting (intake and exhaust) Check PVC pipes for blockages, cracks, proper slope | Annually | 2 · Confident | 15 min | Blocked exhaust = CO risk and unit lockout. |
Replace condensate neutralizer Condensing models only — neutralizes acidic condensate | Every 1–2 yrs | 2 · Confident | 20 min | Saturated neutralizer allows acidic water into drain — corrodes pipes, may violate local code. |
Gas line and connection check Soapy water on all fittings at the unit | Annually | 2 · Confident | 5 min | Gas leak. Leave immediately and call gas company if smell detected. |
Recommended tools & materials
Tankless electric water heater — brands include Stiebel Eltron, Rheem, EcoSmart. No combustion, no flue. Scale is still the main enemy. High electrical draw — typically 150–200 amps for a whole-home unit.
Maintenance tasks
| Task | Cadence | Skill | Time | Consequence if skipped |
|---|---|---|---|---|
Descale heating chambers Circulate vinegar or descaler — same pump kit process as gas tankless | Annually (6 mo in hard water) | 2 · Confident | 1 hr | Scale on heating elements causes burnout — replacement is a significant repair on tankless electric units. |
Clean inlet filter screen Screen at cold inlet — remove, rinse, reinstall | Annually | 1 · Beginner | 10 min | Flow restriction causes activation failures and uneven temperature. |
Inspect dedicated circuit breakers Multiple 40–60A breakers — check for heat or tripping | Annually | 2 · Confident | 5 min | Loose connections at high amperage cause arcing — a fire risk. |
Check heating element continuity Multimeter test | Every 5 yrs | 3 · Advanced | 30 min | Failed element = no hot water. Early detection lets you plan a repair instead of an emergency call. |
Recommended tools & materials
Heat pump water heater — brands include Rheem ProTerra, AO Smith Voltex, Bradford White AeroTherm. 3–4x more efficient than standard electric. Has an air filter most homeowners don’t know about. Lifespan 13–15 years.
Maintenance tasks
| Task | Cadence | Skill | Time | Consequence if skipped |
|---|---|---|---|---|
Clean air filter Washable filter on intake — rinse and dry fully before reinstalling | Every 2–3 months | 1 · Beginner | 10 min | Restricted airflow drops efficiency and causes the unit to fall back to electric resistance heating — losing all energy savings. |
Check and clear condensate drain Unit pulls moisture from air — drain line can clog like an AC line | Annually | 1 · Beginner | 10 min | Blocked condensate = water damage, error codes, potential mold. |
Flush sediment from tank Same drain flush process as standard tank heaters | Annually | 2 · Confident | 30 min | Sediment reduces capacity and efficiency — same failure mode as any tank. |
Inspect / replace anode rod Sacrificial corrosion protection — same as standard tank | Every 3 yrs | 2 · Confident | 45 min | Tank corrosion from inside — same failure mode as gas/electric tank. |
Verify operating mode Confirm set to Heat Pump or Hybrid — not Electric only | Seasonally | 1 · Beginner | 2 min | Units default to electric resistance after power outages — you lose all efficiency gains silently. |
Recommended tools & materials
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