A water heater is one of the largest and most expensive home systems to replace. Knowing the main types, typical lifespan, and warning signs helps you plan instead of reacting to a failure.
Draft. Some reference links and cost figures are still being verified.
A water heater is one of the largest and most expensive home systems to replace. This page covers the main types, what they cost, how long they last, what to check before you call someone, and what the codes require.
| Question | Short answer |
|---|---|
| How long does it last? | Storage tanks typically last 10 to 15 years. Tankless units are commonly cited at about 20 years. |
| When should I plan a replacement? | ENERGY STAR advises considering replacement once a tank passes 10 years, before it fails. |
| What does it cost? | 2026 cost guides put a typical replacement near $1,348 on average (Angi). Tanks run about $880 to $1,830, and tankless about $1,400 to $3,900. |
| When do I need a pro? | Gas lines and venting, electrical circuits, relief valve work, and any leak from the tank body. |
A storage tank keeps a set volume of water hot and reheats it as water is drawn off. Gas tanks use a burner under the tank and vent exhaust through a flue. Electric tanks use resistance elements inside the tank. A tankless (on-demand) unit heats water only while it flows, so it needs enough gas or electrical capacity to meet peak demand. Heat pump water heaters move heat from the surrounding air into the tank, which uses much less electricity than a resistance element.
| Type | How it heats | Typical lifespan | Efficiency reference | Installed cost (2026 guides) | Best fit | Tradeoffs |
|---|---|---|---|---|---|---|
| Gas storage tank | Burner heats a stored tank | 10 to 15 years | ENERGY STAR: UEF of 0.81 or higher for 20 to 55 gallons; 0.86 or higher above 55 gallons | About $880 to $1,830 for a tank | Homes with a gas line and steady hot water use | Standby heat loss; needs proper venting |
| Electric storage tank | Resistance elements heat a stored tank | 10 to 15 years | Check the UEF on the yellow EnergyGuide label | About $880 to $1,830 for a tank | Homes without gas; simple installation | Higher operating cost than a heat pump model |
| Heat pump water heater | Moves heat from the surrounding air into the tank | Check the manufacturer warranty | ENERGY STAR integrated units: UEF of 3.30 or higher | About $2,500 to $4,800 installed | Warm space with airflow, such as a basement or utility room | Cools the space it draws from; needs room and airflow; less efficient in cold rooms |
| Gas tankless | Burner heats water as it flows | About 20 years (DOE) | ENERGY STAR gas tankless: UEF of 0.95 or higher | About $1,400 to $3,900 | Variable demand; space for wall mounting | Needs adequate gas supply and venting; flow is limited by GPM; scale reduces flow over time |
| Symptom | Possible cause | Check first | Call a pro if |
|---|---|---|---|
| Rusty or discolored hot water | Corrosion inside the tank, or sediment | Drain a bucket of water from the drain valve to see whether sediment is present | Color persists after flushing, or the tank is near the end of its life |
| Rumbling or popping | Sediment on the bottom of the tank | Note when the noise happens | The noise continues after a flush |
| Water pooling at the base | Leak from the tank body or a fitting | Dry the area and watch where the water comes from | Any leak from the tank body; this usually means replacement |
| Relief valve dripping or discharging | Excess pressure, a missing expansion control, or a faulty valve | Check whether the discharge is constant or occasional | Any ongoing discharge. Do not cap or plug the valve. |
| Lukewarm water or running out early | Failing element or burner, or a unit too small for demand | Check the thermostat setting | Recovery is slow or water runs cold |
| Gas smell or yellow flame | Combustion or venting problem | Leave the area | Call the gas utility right away. Do not troubleshoot gas burners yourself. |
With power or gas off, a homeowner can drain a storage tank to clear sediment, check the thermostat, and test the relief valve by lifting its lever. Gas connections, venting, electrical circuits, relief valve replacement, and any tank replacement should be done by a licensed plumber or HVAC technician. Replacing a water heater is a job for two people with the right tools, and a tank of 40 to 50 gallons weighs several hundred pounds when full.
| Task | How often | Notes |
|---|---|---|
| Look at the base and fittings | During routine checks | A drip at a fitting may be repairable. A leak from the tank body usually is not. |
| Flush sediment | Per the manufacturer's manual | Intervals depend on water quality. Hard water needs more frequent flushing. |
| Inspect or replace the anode rod | Per the manufacturer's manual | The rod sacrifices itself to protect the tank from corrosion. Water quality affects how quickly it wears. |
| Test the temperature and pressure (T&P) valve | Per the manufacturer's manual | A valve that will not reseat or keeps dripping should be replaced by a pro. |
| Check the thermostat setting | Once a year | Set it to a comfortable level. Higher settings raise energy use and scald risk. |
Water heater rules come from the plumbing and mechanical codes most US jurisdictions adopt, plus local amendments. These rules come up most often:
| Jurisdiction | Fee | Notes |
|---|---|---|
| Village of Kildeer, IL | $25 processing fee plus $75 permit fee | One required final inspection; re-inspection $100 |
| Deerfield, MA | $100 water heater replacement fee | Re-inspection $50; work done without a permit doubles all fees |
| Delaware County (health department) | $60 residential application fee | Permit application for residential water heaters |
| Rocklin, CA | Over-the-counter permit | Storage tank replacement handled at the counter |
| Condition | What changes | Advice |
|---|---|---|
| Cold winters or unheated garages | Heat pump units draw cooler air and run less efficiently; tanks lose more heat in cold rooms | Install in a heated space where possible. Check the manufacturer's guidance before adding an insulation blanket. |
| Hard water | Scale builds up on elements and in tankless heat exchangers. DOE notes scale can restrict flow in tankless units. | Flush more often, as the manufacturer specifies, and consider water treatment. |
| Water softener installed | Softened water can change how quickly the anode rod wears | Inspect the anode rod on schedule and mention the softener to your installer. |
| Coastal or humid areas | Corrosion around fittings and exposed piping | Check fittings more often and specify corrosion-resistant connections. |
| Type | Typical installed range | Main cost drivers |
|---|---|---|
| Tank replacement (gas or electric) | About $880 to $1,830 (national average replacement about $1,348) | Size, fuel type, and any venting or gas-line work |
| Heat pump water heater | About $2,500 to $4,800 | Installation space, electrical work, and rebates |
| Gas tankless | About $1,400 to $3,900 | Gas-line upgrade, venting, and how many units are installed |
These are estimates from published 2026 guides. A tankless conversion often costs more than a like-for-like tank replacement, because the gas line and venting may need upgrades. Get at least three written quotes that state the model, capacity, efficiency rating, and what is included.
Size a water heater to peak demand, not just the number of people in the home. For tankless units, DOE's guideline says to total the flow rates of fixtures that could run at the same time, and to calculate the temperature rise from the incoming water temperature to about 120°F. ENERGY STAR's typical flow figures are 2.5 GPM for a shower or tub, 3.3 GPM for a clothes washer, 2.2 GPM for a kitchen or bathroom sink, and 1.3 GPM for a dishwasher. For tanks, ENERGY STAR sets minimum First-Hour Ratings of 51 gallons per hour for gas storage and 45 gallons per hour for heat pump and electric storage units. Ask the installer for the first-hour rating of the unit you buy.
Check the age on the serial number label. ENERGY STAR advises considering replacement once a tank passes 10 years. Rust, leaks, noise, and slow recovery are signs that replacement may be near.
ENERGY STAR says its certified heat pump water heaters can use about 70 percent less energy than a standard electric model. Savings depend on the space the unit draws air from, the electric rate, and how much hot water your household uses.
Often yes. Requirements vary by location. Some places treat a like-for-like tank swap as a simple over-the-counter permit, while others require an inspection. Ask your local building or health department.
A tank suits homes with steady hot water use and a simpler installation. A tankless unit suits variable demand and homes with space for wall mounting, but it may need gas-line and venting upgrades. Compare total installed cost, not just the unit price.
The temperature and pressure (T&P) relief valve opens to release water if the tank overheats or pressure gets too high. A valve that discharges regularly signals a problem that needs a pro, and the valve should never be capped.
| Term | Meaning |
|---|---|
| UEF (Uniform Energy Factor) | A measure of water heater efficiency. Higher is more efficient. |
| FHR (First-Hour Rating) | The gallons of hot water a storage unit can deliver in the first hour of use, starting from a full tank. |
| GPM (gallons per minute) | The flow rate a tankless unit can supply. Used for sizing. |
| T&P valve | Temperature and pressure relief valve. A safety device that releases water if the tank overheats or over-pressurizes. |
| Anode rod | A metal rod inside the tank that corrodes first to protect the tank. |
| Expansion tank | A small tank that absorbs pressure as water heats in a closed system. |
| Temperature rise | The difference between incoming water temperature and the output temperature. Used to size tankless units. |
Sources reviewed November 4, 2026. Independent professional review: pending. Cost data comes from 2026 cost guides and should be confirmed with local quotes. Confirm local rules with your building department.
| Service | When you need it | Typical cost (2026 guides) | DIY or pro | Permit usually? |
|---|---|---|---|---|
| Element or thermostat replacement (electric) | No hot water or lukewarm water in an electric tank | About $200 to $400 installed, per Charles & Hudson | Licensed plumber | Usually not for a component swap |
| Gas burner or control repair | Pilot or burner fails, or the unit won't ignite | Repair averages about $616 nationally (Angi); parts vary | Licensed plumber or HVAC technician | Usually not for a like-for-like repair |
| Leak repair at a fitting | Drip at a valve or connection | Often a small job; a leak from the tank body usually means replacement | Licensed plumber | Usually not |
| Relief valve replacement | Valve drips or fails its test | Valve price plus labor; get a written quote | Licensed plumber | Usually not |
| Service | When you need it | Typical cost (2026 guides) | DIY or pro | Permit usually? |
|---|---|---|---|---|
| Flush sediment | Rumbling, popping, or reduced capacity | About $75 to $250 with a plumber (HomeAdvisor); average about $160 | Homeowner with the power or gas off, or a pro | No |
| Anode rod inspection or replacement | Inspect per manufacturer's manual; Angi suggests replacing at least every five years | About $250 to $450 installed (LatestCost); parts about $20 to $50 (Angi) | Licensed plumber for most homes | No |
| Thermostat and temperature check | Once a year | Free to check; set to a comfortable level | Homeowner | No |
| Service | When you need it | Typical cost (2026 guides) | DIY or pro | Permit usually? |
|---|---|---|---|---|
| Tank replacement | Failed or near end-of-life tank | About $880 to $1,830 for a tank; national average replacement about $1,348 (Angi) | Licensed plumber | Usually yes |
| Heat pump water heater | Replacement with a more efficient unit | About $2,500 to $4,800 installed (PickHVAC; Rising Sun Arts Centre) | Licensed plumber or HVAC technician | Usually yes |
| Tankless conversion | Replacement with on-demand heating | About $1,400 to $3,900 (Angi); gas-line or venting upgrades add cost | Licensed plumber, and a gas technician for gas work | Usually yes |
| Expansion tank and relief valve discharge piping | Required in some closed systems and at replacement | Not verified; get itemized quotes | Licensed plumber | Usually yes with replacement |