Typically, you need to hire a licensed plumber to install a water heater. Familiarize yourself with laws in your state. In many states, contractors must carry a valid plumbing license to install a water heater.

As you research professionals, take note of the specialties that plumbers list on their profiles or websites. It’s a good idea to choose a plumber who specializes in water heater installation rather than a generalist. And because water heaters consume a lot of energy, be sure to also look for an installer who offers energy-efficient options.

Before you hire a plumber, be sure to also: 

• Read their reviews and ask for references if they don’t have many testimonials.

• Get at least two or three quotes from different plumbers to ensure you’re paying a fair price.

• Ask them if they’re familiar with your specific water heater. Have the make and model ready and let them know if it’s gas, electric, conventional or tankless. 

• Find out if they offer warranties for their workmanship or parts. This may help you save on future repairs if the installation isn’t done correctly and your unit requires future repairs. 

The national average cost to install a new water heater ranges from around $700 to $2,000,* according to Thumbtack data. Prices are similar across all ranges for gas, electric and tankless water heaters, with electric water heaters tending to be slightly less expensive than the other options.

The main cost behind replacing a water heater is its capacity. For example, a 40-gallon water heater can cost around $1,500* to replace at the low end, whereas a 75-gallon water heater can cost around $2,000* at the low end. 

Other costs include labor, which is usually fairly low because (in most cases) it only takes a couple of hours to install a new water heater. 

*Data on file at Thumbtack. For a personalized cost estimate, request a quote from a professional.

Water heaters typically have a lifespan of about six to 12 years, so if yours is in this age range and starting to malfunction, it may be time to replace it. If the water heater tank is leaking or showing signs of rust, it’s definitely time to consider a replacement.

Not all water heater problems require replacement, however. For example, if your water heater is producing less hot water than usual, repairs may be sufficient. The problem could be a faulty thermostat or thermocouple (for gas water heaters) or a broken heating element (for electric water heaters) — both of which are relatively inexpensive compared to the cost of a new water heater.

Your water heater may also need to be drained and cleaned out to remove sediment buildup in the bottom of the tank. Similarly, leaky pipes can also usually be repaired without replacing the entire water heater.

Installing a new water heater can be hard work, but the process itself is relatively simple. Here’s what the average water heater installation entails:

• A plumber will begin by shutting off water, electricity or gas to the existing unit.

• Next, they’ll drain the existing water heater.

• After that, they’ll remove the existing water heater, then bring in the new one and hook up water, electrical or gas connections. 

• Once the new connections are made, the installer will restore water, electric or gas service and check all connections to ensure there are no leaks.

Your installer may also offer water heater removal services. If they do, they’ll remove the old water heater from your property and dispose of it for a small fee.

It generally takes a plumber two to three hours to install a new water heater. Here are some factors that can affect this time frame:

• Complications like small spaces or the need for extensive plumbing repairs in addition to the water heater replacement can increase the timeframe to between four and eight hours.

• Switching between electric and gas water heaters may take a day or more because the installer may need to run electrical service or gas lines to the site.

• Switching from a tank water heater to a tankless water heater may take as much as a day because the installer will need to reroute plumbing and electricity to hook the tankless heater up properly.

Highly skilled DIYers may be able to install water heaters without the assistance of a professional. However, there are a couple of considerations to keep in mind: 

• Safety risks: Water heater installation does come with some potential risks. It requires someone capable of safely making gas or electrical connections, both of which can be dangerous if not done properly. A qualified professional or licensed plumber will be able to hook these utilities up safely while also ensuring that water connections are leak-free.

• Warranties: It can be costly to repair or replace a water heater. Hiring an approved professional helps you avoid accidentally voiding the warranty.

• Hassle: Professional water heater installers and plumbers will often handle the removal and disposal of the old water heater for you, which can save a lot of hassle. 

For these reasons, it’s usually best to hire a water heater installation professional near you