Hot Water Heater Troubleshooting

Gas and electric hot water heater troubleshooting and repair guide. How to troubleshoot WH tank leaking, when pilot light goes out, sediment build-up, rotten egg smell, the noise, rusty hot water, thermocouple...

Hot water heater troubleshooting article will help you learn about common problems that might affect your WH, how to use the symptoms for easier troubleshooting and what is needed for successful repairs.

Some problems with WH are simple and easy to fix. The solution can be found here or any other DIY article or forum. As long as you have some plumbing, electrical and gas skills, and the right tools, you can do the repairs without calling the expensive plumber.

Hot Water Heater Troubleshooting - Common Problems

The following symptoms and problems are common on tank type WHs using both fuel type; electricity and gas (natural and propane, LP). Keep in mind that gas WH are more complex machines than electrical so troubleshooting is harder. Common problems are below while electric WH troubleshooting and how to troubleshoot gas WH are separate articles.

Water heater leaking

One of the frequent complaints found on forums and in many reviews is the puddle of water found under the WH. Leaking is what identifies with this symptom. The reason for the leak can be found when the tank is rusty, TPR valve discharges an excessive pressure, or one of the fittings is loose. How to fix water heater leak is one of the problems this article will deal with.

emergency plumber

Sediment and lime build-up

Almost every heater is affected by the hard water and this is what increases the chance of premature tank failure. Cleaning sediments out from the heater regularly is what eventually saves money, as the WH performs better and more efficient.

Sediment build-up affect the performance of your WH while it can cause the rotten egg smell and annoying popping noise. This water heater troubleshooting article will cover ways how to control sediment build-up and how to remove it.

Water color change

How and why water inside the WH tank is changing read further. This troubleshooting guide will cover problems that are related to milky, discolored, and rusty hot water and how to repair it.

Rotten egg smell

Smelly water is very unpleasant problem. You open the hot water tap and there is a terrible sulfur odor which reminds on rotten egg. How to troubleshoot rotten egg odor and how to prevent it is what this article will cover.

Water heater noise

Is your WH making ticking, popping, sizzling, pounding, humming or clicking noise? Or the plumbing pipes are making loud noise which is known as water hammer?

Cold water sandwiches

"Cold water sandwiches" are most of the time found on tankless heaters but can also be seen in storage tank type WH. Fluctuation in the temperature is what makes your shower hot-cold-hot-cold or known as cold water sandwich.

Low pressure

How to do hot water heater troubleshooting when your water heater has a low water pressure. What causes the low pressure and how to fix it?

Not enough hot water or temperature is too low for shower

How many times did you experience lukewarm water after 10 minutes of showering? What causes the problem when there is not enough hot water for your shower or dishes, and how to do repairs. Is it a heating element, gas burner, dip tube or something else?

Related articles

Troubleshooting pilot light problems on gas units. How to fix when pilot light goes out, pilot does not light, pilot won't stay lit, pilot flame is too small or too large.

Gas heater installation instructions. Step-by-step guide how to install units properly, including tank-type models from Rheem, Bradford White, AO Smith, Reliance, Kenmore, GE, American and other manufacturers.

Why checking the burner flame in water heaters is important? What should you do if the flame is yellow, orange or blue color? What are the most common problems if the gas is not burning properly and how to avoid it?

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