Why Installing a Water Heater Yourself Is Rarely The Right Move

Stacy Sare Cohen
Written by Stacy Sare Cohen
Reviewed by Joseph Wood
Updated May 6, 2022
Father and son wash dishes in the kitchen sink
Photo: MoMo Productions / DigitalVision / Getty Images

When your water heater is on the fritz, put down the wrench and pick up your phone instead

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We all love the benefits of hot water: sparkling dishes, unsoiled bright whites, and a hot shower to soothe our tired muscles after a long day. But when our water heater goes kaput, it can be a major inconvenience and a nuisance. To save some cash, you might wonder if you can install a water heater yourself. 

Put simply, installing a water heater is no weekend DIY project. In fact, it’s best to leave the task to a licensed plumber––or you could be facing major safety, financial, and legal risks. 

Here’s why you shouldn’t install a water heater on your own:

Installing a Water Heater Requires Professional Training

Water heater installation requires plumbing, electrical, and carpentry skills. One of the most important decisions a professional makes is installing the right-sized water heater for your home. A tank that is too small will struggle to heat your home properly and wear out faster. While most homes require 50-gallon tanks, a 60-gallon tank may be needed in a home with heavy shower and laundry use. 


Formal training teaches aspiring plumbers how to work on water and gas lines, including installing the proper fixtures and checking for pressure issues or gas leaks. One tiny DIY misstep could mean danger including:

  • Over-tightening a gas control valve, which could cause a gas leak and lead to a fire

  • Improper ventilation, which is a common precursor to carbon monoxide poisoning

  • Improper supply line connections, which puts undue stress on drainage systems and can allow cross-connections between unsafe sources, like a heating pipe

  • Leaks in electric lines or gas valves, which can trip breakers and trigger automatic shutoff 


Plumbers also learn the electrical skills necessary to connect gas or electric water heaters to a breaker box. Faulty electrical work could lead to issues such as:

  • Loose wires in your water heater, which can trip the water heater reset button.

  • A water heater that keeps flipping the circuit breaker

  • Blown fuses and tripped circuit breakers, which can lead to fires and fried appliances 


Aside from plumbing and electrical technicalities, Installing a water heater may require maneuvering drywall, grounding plumbing pipes, and leveling the base of your water heater. When the install gets tricky—it likely will—a knowledgeable pro can handle complicated scenarios like:

  • Installing your system in locations that are difficult to access

  • Building a larger installation space for larger, newer water heaters

  • Understanding when to install water heaters in attics to meet new size regulations and building codes, which may require construction

  • Supplying proper insulation around the tank

The Water Heater Can Explode or Start a Fire

Hot water heater in basement of house
Photo: Jupiterimages / Stockbyte / Getty Images

Gas water heaters are powered by burning combustible fuel. But despite all the pleasures of hot water, combustible fuel is highly flammable. And if your water heater isn’t installed properly it can cause a fire, explosion, or carbon monoxide poisoning.

Improper installation can lead to serious safety and health risks, such as:

  • Gas leaks

  • Carbon monoxide poisoning due to improper ventilation

  • Water damage due to improper connections between the water heater and the right supply lines, which affect its ability to drain water properly. 

Your Home Insurance Company and Manufacturer’s Warranty Won’t Cover Damages Incurred from Faulty Self-Installations 

If your water heater isn’t installed by a licensed plumber, your home insurance company will likely refuse to pay for damage caused by your water heater. Paying out of pocket can cost thousands of dollars if a water heater explodes and floods your home––or worse, your neighbors’ house.

The water heater manufacturer will also leave you hanging in the lurch if there’s a problem with your DIY installation. In fact, you won’t even be able to register your product warranty without a plumber’s licensing details.

You Need to Apply for a Permit and Comply With Building Codes

Most municipalities require permits for water heater installations. Doing this without a permit is risky because you could be fined if caught—especially when you go to sell your home in the future. 

Water heaters and hot water storage tanks must comply with your local and state regulations, requiring:

  • Inspections to protect inhabitants and visitors from potential safety risks

  • Placing your water heater in a location that provides access to observation, maintenance, servicing, and replacement

  • Displaying pressure limits on the metal of the water heater

  • Providing the appropriate elevation of the system

  • Following proper seismic specifications in regions prone to earthquakes

  • Assuring the correct circulation for the water heater

  • Including anti-siphoning devices

  • Installing pressure relief valves and temperature relief valves where appropriate

  • Using temperature relief valves that don’t exceed 210 degrees Fahrenheit and pressure relief valves that don’t exceed 150 psi

If these state regulations seem complicated, it’s because they are. While different municipalities list different building codes and regulations, a licensed plumber in your state will be familiar with them. Failure to comply with these regulations will result in possible safety issues and fines.

Reasons Why You Shouldn’t Install a Water Heater Yourself Explained

As you can see, hiring a licensed plumber can not only help you eliminate risk, it can save you from severe headaches. A 40- to 50-gallon water tank costs an average of $900 including installation, while tankless water heaters will run about$2,250. So do yourself a favor, and leave the Tylenol in the medicine cabinet (for now), stay safe, avoid heavy fines, and a possible lawsuit.

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