How much does it cost to replace an old water heater?

Water heater replacement cost with labor

The cost to replace an old water heater with a standard tank is $650 to $2,500 installed, materials and labor included. Removal, permits and code items can sit on top of that. Before your deadline, get a licensed plumber's written bid for the full job. Then ask the seller for that figure as a credit or as a completed replacement.

Key takeaways

• A tank water heater typically lasts about 10 years. Gas tanks can start failing sooner than electric ones.
• If a year of repairs would cost more than 10% of a new install, the inspector trade group says replacing parts is probably not worth it.
• Ask each plumber whether removal, the permit, an expansion tank and seismic straps are in the price. Each one can be a separate line.

How old is too old for a water heater?

There is no hard cutoff. The International Association of Certified Home Inspectors (InterNACHI) puts the typical tank at about 10 years. It ties the rest to installation, water use, build quality and maintenance. Hard water shortens it, because mineral buildup cuts the unit's efficiency.

Water heater maker A.O. Smith is more specific. Its gas tanks may begin failing around 6 to 10 years, and electric tanks generally last closer to 10 to 12. A 14-year-old tank is past both ranges.

Age alone tells you the unit is near the end. What the inspector saw at the tank tells you how near.

Is an old water heater dangerous?

Watch for a leak. InterNACHI calls a puddle under the heater a telltale sign that a new one is probably in order. Fixr ties water at the base to corrosion or a cracked tank, and rust-colored water to corrosion inside. A report that notes rust at the fittings or base is describing that wear, not just a birthdate.

Gas units add a second risk. InterNACHI says water heaters belong in well-ventilated areas for "fire safety requirements and carbon monoxide buildup." If your report flags the vent, the flue or the gas line, have a licensed plumber look at it before your deadline and before you talk money.

If you smell gas at the house, leave the area and call 911 from somewhere well away from the leak. Then call the gas utility, then a licensed plumber. If you suspect carbon monoxide, get outside to fresh air, then call 911.

What is a fair price for a water heater replacement?

National guides and one local plumber price the same swap at different scopes. Match the row to your tank's size and fuel.

Fixr prices the extras separately. Many plumbers include hauling away the old heater, but if yours charges extra, Fixr puts it at $75 to $500. Permits run $25 to $1,500. Fixr says most local building departments require a permit to replace a water heater.

Older homes may need code work too. MV Plumbing says older homes in parts of Boston, Worcester and Cambridge often need an expansion tank ($125 to $200), seismic straps ($50 to $100) and updated relief valve discharge piping, which it does not price.

Here is a worked example for a 50-gallon gas tank in an older home in MV Plumbing's area, using its local figures:

The relief valve piping is not in that total. MV Plumbing says removal of the old heater should be in the quote, so confirm it. A plumber's written bid prices both, along with anything else your tank needs.

Should you repair it or replace it?

For an old tank with problems, replacement usually wins. At 10 to 15 years with frequent problems, A.O. Smith says replacing usually makes more sense than more repairs. InterNACHI's test: if a year's repairs cost more than 10% of buying and installing a new heater, new parts are probably not worth it.

On the worked example, that line sits at a tenth of $925 to $1,700, or $92.50 to $170 a year.

• An anode rod, the part that protects the tank lining from corrosion, costs around $50. That passes.
• Replacing a gas control valve usually costs $300 to $500. That fails, so ask for the replacement.

What should you ask the seller for?

Get the bid first. A licensed plumber can look at the tank, confirm its age and fuel, and put the full scope in writing. How to get repair estimates during the inspection period covers booking that visit fast.

Then pick the form of the ask:

• A credit for the plumber's total, if you would rather choose your own plumber after closing. Budget for a licensed plumber, not a weekend project: Fixr says many areas require one to meet local codes and permit rules.
• A completed replacement before closing, with the permit, if you want the work finished and inspected first.

Put the line in writing with scope, trade and figure. What to ask for after a home inspection shows how it sits next to your other items. The buyer repair request letter template gives you the wording.

What if the seller says no?

You still have choices. Counter with a smaller credit, ask for a price reduction instead, or accept the house and budget the plumber's figure yourself. A bid turns this finding into a known cost. When to walk away after a home inspection covers the cases where the whole list changes the deal.

Your contract sets the deadline and what you can do after a refusal, so confirm both with your agent.

Should you flush a 20-year-old water heater?

Not before closing, and not yourself. A 20-year-old tank is well past every lifespan on this page. InterNACHI warns that the drain valve used for flushing is usually plastic and easy to break, so leave the tank to the plumber on the bid visit.

Does a tankless unit make sense as the replacement?

It costs more up front. Fixr puts a tankless unit at $1,000 to $4,000 installed. If you want one, ask the plumber to bid both, and ask the seller for the tank figure.

How do I know what the rest of my report is worth?

The water heater is one line on the plumbing side. Kept prices every line of an inspection report for $79, usually under 4 hours, and marks the ones that need a professional quote.

If the water heater is one finding of many, upload your inspection report to Kept and spend your remaining days on the bids that need a plumber.

Sources

• Bob Vila, "Water Heater Replacement Costs and Lifespan"
• Fixr, "How Much Does Water Heater Installation Cost?"
• MV Plumbing, "Water Heater Replacement Massachusetts Cost Guide"
• InterNACHI, "Estimating the Lifespan of a Water Heater"
• A.O. Smith, "Water Heater Repair: Things to Consider"
• Pipeline and Hazardous Materials Safety Administration, gas leak emergency response
• U.S. Consumer Product Safety Commission, Carbon Monoxide Information Center