Troubleshooting Water Heaters
Problems and Repair Guide

Plumbing toolsImage by chiplanay from Pixabay

Troubleshooting water heaters and a repair guide.

Explore common heating problems, causes, symptoms, and tips on how to fix: leaky water tank, no hot water, not enough hot water, cold water sandwich, sediment, and scale build-up, noise, bad odor, gas valve problems, pilot, thermocouple and other water heating issues.

DIY instructions and how to get help! 

In this article:

  1. Leaking
  2.  Condensation
  3.  Dripping
  4.  Thermostat problems
  5.  Sediment build-up
  6.  Discolored water
  7.  Corrosion
  8.  Rotten egg odor
  9.  Water hammer
  10.  Heat traps
  11.  Noise
  12.  Pilot light problems
  13.  Cold water sandwich
  14.  Bulging
  15.  Flame issues
  16. Slow hot water delivery
Rheem gas water heaterRheem gas water heater

If you require professional assistance, contact a local water heater expert today!

If you need HELP contact an expert today!

A troubleshooting guide can be used for repairing most of the electric and gas-powered water heaters sold in the US and Canada, including; Rheem, AO Smith, Bradford White, American, State, GE, Ruud, Whirlpool, others.

Keep in mind that symptoms or signs of water heater failure are very similar among different manufacturers, and many are the same, so directions for one brand and model can be applied to others.

To have a better understanding of propane, natural gas, and electric heaters, we recommend you become familiar with articles on how these units work and their main parts. Once you collect all the necessary information, troubleshooting water heaters become much easier.

Heater's problems are not complicated to diagnose, and if DIY home and plumbing projects are not strange to you, and you have the necessary tools, skills, and the right guide, then you can successfully troubleshoot a water heater without calling a plumber.

Note: Troubleshooting water heaters using gas and electricity should be performed by a qualified plumber or HVAC technician.

If looking for help and fast response, contact networx.com or homeadvisor.com and get Free Quotes from their proven plumbing contractors.

Common problems, causes and, symptoms

To make the hot water heater troubleshooting guide easier to understand and fix the heater as a pro, we have provided a lot of information about common problems, causes, and symptoms of water heating issues. Check it out!

Water heater leaking

A leaky water heater is the most frequent problem reported by many people and is found in many consumer reports. The reason for such malfunction might be that the tank's steel body has corroded up to that level that caused a rupture on the tank, resulting in a water leak.

Another reason is the water discharge from the temperature and pressure relief valve (TPR) due to overheating.

If there is a puddle of water on the floor and you know that the leak is coming from the top, check out this article, and if you know that the water is dripping from the bottom, then do this.

Condensation

You have found a small puddle of water under the water heater - is the heater leaking, or is it condensation? For proper troubleshooting, keep in mind that condensation is often present on newer models, such as condensing models, as these units are more efficient than older ones.

A typical heater will produce approximately one-half gallon of water vapor during every hour of work. Condensation usually happens shortly after the heater starts. Follow the provided link to learn more about what causes condensation, how to prevent and deal with it.

Dripping valves and fixtures

A puddle of water under the tank-type water heater is often related to water leaking and condensation. But what if there is dripping from the relief valve or a fixture during the unit's recovery cycle and when no hot or cold water is used?

Find out what causes dripping and how to fix it.

Thermostat problems

If the water is too hot or cold, you might have a problem with the faulty thermostat. Use this article to learn how to troubleshoot and replace the water heater thermostat and ensure a comfortable shower – again.

Sediment build-up

Check out this troubleshooting guide to fix the strange noise in the water heater and improve the lower performance. Sediment build-up at the bottom of the tank is the main problem that must be addressed correctly and on time.

Also, learn how to reduce the effects of hard water using a water softener.

If you require professional assistance, contact a local water heater expert today!

If you need HELP contact an expert today!

Discolored water

There are a few reasons why your hot water is discolored, has a milky or rusty appearance, and the anode rod is one of them.

Corrosion

Explore what causes corrosion and how to prevent it so rust doesn't pollute hot water and weakens the structure of the heating system.

Rotten egg odor

Smelly water, also known as sulfur or rotten egg odor, is generated by bacteria due to decomposing sacrificial anode inside the tank.

Find out how to eliminate bacteria from the system using the chlorination procedure. Water heaters that are not equipped with the anode or include powered rods do not have such a problem. See how to fix smelly water.

Water hammer

Water hammer is the hydraulic shock that is loud and destructive to the house plumbing and a heater. Fixing this common plumbing problem is relatively easy. Learn how.

Heat traps issues

Heat traps are installed to increase the heater's energy efficiency, but you can remove them if they are the source of a problem. Since the sound problems such as ticking, clicking, humming or tapping, are often caused by the heat traps, this guide can help you install or remove them.

Noise

The noise inside the water heater is usually associated with two main conditions; water hammer and mineral build-up, but there are also other reasons such as pounding, rumbling, crackling, popping, ticking, and sizzling.

Pilot light problem

"A pilot light goes out", or pilot outage is one of the most common issues when operating gas-fired water heaters. As improper venting is one of the main causes, see what you can do about it; how to prevent and fix the problem.

Find out how properly to light a water heater.

Get Help from a Local Plumber. FREE Estimates!

Cold water sandwich

What to do when the temperature fluctuates from hot to cold and from hot to cold? Check out this guide for an easy fix and comfortable shower with less "cold water sandwich" effect.

Bulging

Common symptoms seen on the heater exposed to excessive pressure are cockeyed nipples of the top of the heater and bulged or reversed bottom of the head. See what can be done about the bulging problem and how to prevent it.

Burner flame issues

Improper gas combustion is dangerous. Is the burner flame yellow and "lazy"? Do you experience slow hot water recovery, the burner doesn't ignite, combustion odor, smoking and sooting, or burner flame floats?

Then, check out the article "how to properly vent a gas water heater" and learn how to fix it. To avoid an even more dangerous situation, check if there is carbon monoxide emission that might lead to gas poisoning.

Slow hot water delivery

Does it take too long to get hot water at the kitchen sink or in the bathroom? Check out what the cause is and what you can do to get hot water faster.

Plumbing crossover

Plumbing crossover - the main reason for complaints such as: “not enough hot water” and “hot water runs out quickly.”

Find out how to prevent, test, and repair it successfully.

Winterizing tankless

Is your tankless water heater malfunctioning due to freezing temperatures? Use this article and see how to avoid the problem with proper winterizing.

AO Smith electric water heaterAO Smith electric water heater

If you require professional assistance, contact a local water heater expert today!

First, recognize the problem

The first thing when dealing with the electric or gas hot water heater troubleshooting is to recognize a problem.

Before the big problem occurs, it is vital to understand the symptoms, does a heater have low performance, uncomfortable temperature, is it still efficient, does it deliver enough hot water, is it heating water at all, and finally troubleshoot and fix it on time.

Electric models are very easy to troubleshoot, while fixing gas heaters is more complicated, but if you know the heating process, unit's anatomy and have basic knowledge, the repair shouldn't be a problem.

Due to the advanced design, tankless is even more complex. Because many models are equipped with the diagnostics system, troubleshooting is easier.

With the proper problem diagnosing, you will save time and money. I have seen and experienced many times that a solution for a water heating problem can be very simple (like low temperature settings or a blown fuse at the breaker) or easy repair by replacing the faulty element (heating element, thermostat...).

The recommendation is to perform the maintenance and service the unit regularly because this is one of the best ways to prevent the problem on the heater and even extend the life of the unit.

YouTube video 1: Troubleshooting gas water heaters

YouTube video 2: How to troubleshoot an electric water heater

Preparing site for troubleshooting

Before trying to fix any of the problems presented in the above text, here are more tips for troubleshooting water heaters and preparing the site for repairs.

  • Turn off both gas and electric power before working on the heater.
  • Shut off the water supply to the heater.
  • Plug the garden hose to the drain valve.
  • Prepare the necessary tools for service.

Conclusion

Keep in mind that the water heater failure and the unit's replacement can be easily avoided if the signs of a potential problem are identified on time.

Some of these issues are easy to fix; some require more time, knowledge, and the right tools. Prevention is the key, so if the maintenance is done regularly and as recommended by the manufacturer, it will bring long service, efficient, and safe operation.

For additional help use the AO Smith website with the links to the service handbooks (in pdf format).

Related articles

Leave a Comment!

[ ? ]

Author Information (optional)

To receive credit as the author, enter your information below.

(first or full name)

(e.g., City, State, Country)

Submit Your Contribution

  •  submission guidelines.


(You can preview and edit on the next page)

What Other Visitors Have Said


air spitting when using faucet 
Had a new gas hot water heater 50 gallon installed in March of 2018. Since it was installed I have had a spitting sound when I turn on the water first …

low water pressure out of hot water heater 
Suddenly over the last few weeks I have noticed very low water pressure coming out of my John Wood Power Vent hot water heater. It isn't something that …

Insufficient hot water and damaged heating element 
As the title says, my Bradford White electric water heater does not produce hot water... actually the upper heating element, when removed, shows a visible …

Gas Hot Water Heater - Lifetime? 
We have the rotten egg smell going, the hot water heater is 12 yrs old. We assume from reading on line it is the anode rod... My question is---Is 12 …

Water Hammer or ... 
Hi, I have a three year old Whirlpool 40 gallon gas water heater and every time I turn on the water, at the sink, shower, washer, anywhere, there are very …

My New CraftMaster water heater makes noise 
I installed this water heater about one month ago. From day one when you open the hot water on any faucet after about 20 seconds there is a loud hum from …

Whirlpool water heater gas 
Water heater pilot light goes out after being lit and burner comes on and brings water temp up. When burner kicks off the pilot goes out as well. But if …

Gas water heater question 
I have a gas fired water heater, cylinder type, with the fan on the top. Every time I want to run my hot water there is a sound from the bottom of the …

Ouch! The Atwood G6A-6E water heater in my trailer is too hot. 
The hot water seems overly hot. I believe this is a waste of energy because the hotter the water, the faster it loses heat. I also scald my fingers when …

No hot water in shower 
Hi, I have an electric water heater, tank type in my basement. I was using hot water last night, and didn't have any problem. There was nothing unusual, …

Why pilot light on my water heater goes out 
Why pilot light on my water heater goes out? We changed the thermocouple and still nothing.

My hot water changed the color 
I have just installed a new Rheem water heater, Fury model and everything was ok, but when I open the hot water tap to use the hot water, I have noticed …

Blowing Elements -Tripping Breakers and Hot ware coming out of Cold Water Supply Line Not rated yet
We purchased a home that was 11 years old. The hot water heater is a Rheem 40 gallon tank. Now when we moved in the hot water heater was not working. …

Click here to write your own.

Popular Articles