How Much Does A Water Heater Cost Installed?

Average cost to install 40 gallon hot water heater

Your water heater may not be the most expensive appliance in your home, but the mess that it can create when it dies can certainly make it the most costly. Every year at Comfort Heroes we inspect thousands of water heaters. Many of the water heaters we inspect can be safely certified for another year of operation. Others, however, have rusted out tanks, substantial mineral deposits, depleted anode rods and seized temperature and pressure safety relief valves. When you’re facing issues like those it may just be in your best interest to replace your water heater before it floods your basement.

Clients ask us all the time, “How long do water heaters usually last?” That can be a tricky question since it really comes down to the quality of the water and how frequently you have it maintained. On average a water heater will last about 7-8 years before it needs to be replaced. However, this number can be substantially doubled (or even tripled!) by performing routine maintenance and installing water filtration. By reading this article you will gain a greater understanding of not only how your water heater works, but also have a better idea of how much a new water heater system will cost if you are faced with that decision.

Electric vs. Gas Water Heaters

The two primary methods of heating water are by gas (either natural gas or propane) and by electricity. Natural gas water heaters tend to operate at about a third of the cost of an electric water heater. An electric water heater may cost slightly less than a gas water heater, but the cost of ownership is substantially higher due to higher utility costs per BTU of heat. The only exception to this rule is when it comes to hybrid electric water heaters which utilize a heat pump and are about as energy efficient as a gas style water heater.

Tank vs. Tankless Water Heaters

A tank style gas water heater will operate at about 60% energy efficiency while a tankless gas style water heater can operate at up to 98% energy efficiency. This means that for every $100 you spend to heat water a gas tank style will allow about $40 worth of heat escape through the exhaust while the condensing tankless water heater will only allow about $2 to escape through the exhaust pipe. That is a substantial energy savings and is one of the main reasons why more of our clients are transitioning to tankless style water heaters.

What Are Water Heater Code Upgrades?

Depending on when your water heater was originally installed your new water heater may require some additional “add-ons” to bring it up to the current plumbing code standards. In the City of Sioux Falls the adopted plumbing code is the 2015 Uniform Plumbing Code. What this means is that if your water heat is old enough to need to be replaced then there is a strong possibility that it is going to need to be brought up to code.

What are some of the most common code upgrades?

Thermal Expansion Tank

As your water heater heats the water the water volume expands. The job of the thermal expansion tank is to absorb the extra water volume so that the excess pressure does not cause undue wear and tear on the water heater and other fixtures in the home. The cost to install a new Thermal expansion tank can range from $279 to $443.

Combustion Air

The National Fuel Gas code requires 50 cubic feet per 1,000 BTU’s per hour of gas appliances in an enclosed mechanical room. This means that if you have a 40,000 BTU/hr water heater, a 80,000 BTU/hr furnace and a 22,000 BTU/hr dryer in an enclosed mechanical room in your basement then the room would need to be unobstructed with 8 foot ceilings and be 365 sq ft or more. If the room is smaller than that then fresh air will need to be brought in from outside of the room so that the gas combust properly in the equipment. If there is not enough fresh combustion air in the room then it is possible for the room to come under negative pressure and carbon monoxide to accumulate. The cost to install a new combustion air intake can range from $279 to $689.

B Venting

Many older plumbing and furnace exhaust vent systems do not meet current code clearances or BTU requirements and could require upgrade. The clearance from a single wall exhaust pipe is 6″ while the clearance from a B vent exhaust pipe is only 1″. If clearances cannot be made  then it may be necessary to tin the walls. The price to install new b venting from the water heater or furnace can cost anywhere from $689 to $1,682

Gas Valve, Drip Leg, Union

The gas piping also must be brought up to code with a new water heater. This means that there must be a gas shut off valve, drip leg and union present. The purpose of the gas valve is to shut off the gas in the event of a leak or future replacements. The job of the drip leg is to catch any moisture, dirt, sediment, pipe dope or other impurities that could travel through the gas pipes to the appliance. The union makes the system easier to service. The cost of replacing the gas cock and water heater gas supply per code is $259.

Shut Off Valve – 

Replacing a water heater is the perfect time to install a new water heater house shut off valve. A valve to turn off the water is not only a code requirement, but is also incredibly handy in the event of a leaky water heater. Modern day ball valves are also much more reliable than older globe style valves. Installation of a new water heater shut off valve costs between $128 and $279.

Average Cost of A Water Heater Installation

As I said earlier, it is impossible to give an accurate assessment of what an HVAC system will cost without considering the size, design and layout. However, we can get into the right ballpark.

  • You can expect to spend $1,150 to $2,300 for a tank style water heater.
  • A tankless water heater can cost anywhere between $4,200 and $12,000 for a residential hot water system.

The spectrum on new water heater costs as well as code upgrade costs are fairly broad and that is because there are so many difference between homes, sizes, and what your home may need is not necessarily what your neighbors house may need.


If you think you may need a new water heater or endless hot water tankless system then call our team and have one of our licensed service experts visit with you. We can figure out what water heater you need and go over all the different options available to you in order to design the perfect system for your family and your budget.

About Comfort Heroes

Comfort Heroess, LLC , rated A+ by the Better Business Bureau, was founded in 2014 by Alan Gentry. His vision was to build a home service company that clients could turn to for just about every problem a homeowner could face. Since then Comfort Heroes has grown to offer plumbing, heating, cooling, sewer, drain, remodeling and insulation services. For more information please call (605) 202-2020 or visit