Water Heater Not Working Properly? 7 Common Causes (and How to Fix Them)

Having no hot water is a major concern, as you won’t be able to comfortably bathe or effectively wash dishes until you can get your water heater working again. Numerous issues can lead to a water heater not working. Some of them you can quickly fix yourself, while others will require you to call a plumber. Let’s look at the most common problems you might encounter and what it takes to overcome them.

1. Electricity or Gas Supply Issues

Water heaters rely on either electricity or gas to produce heat, meaning they obviously won’t work if the supply is cut off for any reason. An electric water heater can sometimes experience an electrical fault, such as a short circuit, that causes it to trip the circuit breaker. Resetting the breaker if it’s tripped should make your water heater turn on almost immediately.

If the breaker trips a second time, it usually indicates that the unit has a potentially hazardous electrical issue that could cause major damage or lead to a fire. As such, you should leave the breaker switched off until you have the unit inspected by a plumber.

Determining whether the gas supply is interrupted can be more difficult, as this issue is often caused by a faulty or worn-out gas valve. It’s also possible that your home’s gas supply was shut off. If you have any other gas appliances, it’s a good idea to check if they still work. If none of them do, you’ll need to contact the gas company to determine what the problem is.

2. Pilot Light Is Out

If you have an older gas water heater with a standing pilot light, the first thing to check is that the flame is still lit. Sometimes a draft can blow a pilot light out, and the flame will also immediately go out if the gas supply is temporarily disrupted. If the pilot is out, your water heater should come on within a minute or so after you relight the pilot.

When you push the pilot knob in, you should hear gas starting to flow and start smelling a faint rotten egg odor. If you don’t, it means that either the gas tube is clogged or the pilot gas valve is faulty. If the flame keeps going out when you release the knob, it means that the thermocouple isn’t detecting the flames because it’s faulty, bent, or dirty.

3. Electric Igniter Issue

Newer gas water heaters rely on an electronic igniter to light the burners instead of a pilot light. The igniter is exposed to extreme heat whenever the water heater runs, which can eventually lead to it failing. You can usually tell fairly easily if the igniter is bad, as most units will start displaying an error code. You can then consult your owner’s manual to see if the specific error code corresponds to an igniter issue or something else.

In some cases, the problem may not be that the igniter is bad, but instead that it isn’t receiving enough power to turn on. It’s also possible that the control board is malfunctioning and not signaling the igniter to come on.

4. Faulty Heating Element

Electric tank water heaters have an upper and a lower heating element. These heating elements sometimes last for the life of the water heater, but various issues can cause them to fail sooner. A failed heating element will usually just lead to the water heater taking much longer to heat, but it can also result in the water never getting fully hot. An electrical fault could even fry both elements and cause you to have no hot water.

One issue that will almost always fry a heating element is dry firing, which is when the element produces heat when it’s not surrounded by water. This can easily happen if you drain the tank and then turn the unit back on before the tank is fully filled. Issues with your home’s water supply can also lead to an air pocket within the tank that results in one of the elements dry firing.

Not flushing the tank often enough is another common issue that can result in the lower heating element burning up. Sediment particles continually form inside a water heater tank as a result of some of the dissolved minerals in the water heater solidifying when heated. The sediment always absorbs heat and creates hot spots when the water heater is on. If the sediment layer builds to the point that it touches the lower heating element, the element can get so hot that the metal melts.

Having a failed heating element fixed typically doesn’t cost more than a few hundred dollars. Nonetheless, most plumbers recommend replacing the water heater itself if it’s more than seven or eight years old.

5. Sediment Buildup

While sediment buildup can result in a failed heating element, it can also cause an electric or gas water heater to heat much more slowly or lead to your hot water running out more quickly. The first issue happens because the sediment blocks some of the heat from the gas burner or the lower heating element from flowing out into the water. The latter issue occurs because the sediment takes up space in the tank, so that it isn’t able to hold as much water. Flushing the tank once or twice a year to remove the sediment not only helps prevent these issues, but it also improves the water heater’s efficiency and helps it last longer.

6. Malfunctioning Thermostat

All tank water heaters have an internal thermostat that measures the water temperature and signals the gas burner or heating elements to turn on and off. The thermostat can sometimes start malfunctioning and not sense the temperature correctly. This normally results in the water heater shutting off before the water is fully hot, but it can also lead to the water frequently getting too hot.

In the latter case, the T&P (temperature and pressure) relief valve will usually open and allow some of the water to drain to reduce the pressure in the tank. If the thermostat fails, the water heater won’t ever come on. The thermostat can also occasionally malfunction and not signal the water heater to run.

7. Broken Dip Tube

The dip tube is a long plastic pipe that connects to the cold water inlet on top of the water heater and extends down to the bottom of the tank. Its purpose is to funnel the incoming cold water to the bottom of the tank so that it doesn’t mix with the hot water at the top of the tank. While it’s somewhat rare, the dip tube can crack or break. A damaged dip tube always results in the water quickly getting colder as a result of the incoming cold water cooling down the remaining hot water in the tank. If the damage is near the top of the tube, you may run out of fully hot water within a few seconds.

A replacement dip tube itself is fairly inexpensive, but the added labor costs usually mean the repair will cost a few hundred dollars. This is another situation where you need to consider how much life your water heater likely has left when deciding whether repair or water heater replacement is the better option.

When it comes to water heater repair in Sacramento, no one beats the experts at Drain Time Plumbing. Our family-owned and -operated company has been providing top-notch water heater services for more than 30 years and can ensure you have sufficient hot water for all of your needs.

We work with all brands of traditional and tankless water heaters, and our team is available 24/7 to respond to any hot water emergencies. For more information or to schedule service, contact us today.