Why is My Hot Water Heater Not Heating?

Have you ever stepped foot into a shower and been blasted by ice-cold water? You jump, you scream, you might even take down the shower curtain trying to get away from the freezing water.

When your hot water heater stops heating the water you use, you notice it at the worst moments, like when wanting to take a hot shower after a long day. Let’s investigate why your hot water heater might not be heating and what you can do to avoid the cold.

What Type of Water Heater Do You Have?

Most homes have either a gas water heater or an electric water heater. They heat water differently, which means they have different troubleshooting steps when you’re not getting hot water from your faucets or showerheads. If you’re not sure what type of water heater you have, refer to the manual for it. If you can’t find the manual, look for a flue.

A gas water heater will have a flue that vents the exhaust fumes. This is required to have a gas water heater installed in a home. An electric water heater will have an electrical cord to power it and no flue or vent.

Gas water heaters can be harder to troubleshoot than electric ones. If you’re not a troubleshooter, call A.B. May to do it for you.

Do You Rent or Own?

If you rent an apartment or home, call your landlord or property manager when you notice your hot water heater isn’t heating water properly. Most rental properties will have a tank water heater or conventional water heater installed - nothing high quality.

They are responsible for fixing issues like heat loss from the water heater or issues with the dishwasher or laundry not getting enough hot water to work. You don’t want to risk causing more harm than good when renting from homeowners or property management companies.

The Most Common Water Heater Not Heating Issues

Gas or Electric Issues

You know if you’re last in the shower, sometimes you get a cold or lukewarm shower because the people before you used up gallons and gallons of hot water. If the first time you’re figuring out you have no water is because of the shower, test different faucets in the home to see if you have hot water in other areas of your home. If you don’t have hot water anywhere, there may be an issue with your water heater.

If you have a gas water heater, see if there are any issues in the area. If it is a propane water heater, check the propane levels. Check all your gas appliances; if none of them work, it’s a gas issue. Call your gas company to find out why.

If you have an electric water heater, check to make sure the breaker hasn’t flipped and the fuse isn’t blown out. Flip the breaker back on or replace the fuse and try again. If you notice other issues with electricity in the house, call the electric company.

A Thermostat on the Fritz

While water heater thermostats are often less prone to failure, they can fail. They can either go out entirely or fail so slowly it takes a while to notice how cold your water is getting. Check the reset button on your water heater – if it pops out, this could indicate that your water is getting hotter than 180 degrees. This means the thermostat could be faulty. Pop the reset button again, give it a few hours, and see if it pops out again.

Pilot Light or Ignition Issues

A gas water heater will use a pilot light, while an electric water heater uses an ignition. There are hybrids of this in natural gas-ignitions, too. If your pilot light goes out and can’t be re-lit, there may be a gas issue along the water heater's lines.

If your electric ignition doesn’t start, it could be a faulty ignition or electrical issues with the unit. This requires a plumber to come out and diagnose for various reasons, from fault equipment to a clogged sensor.

Temperature and Pressure-relief Valve (TPR) Failures

If your TPR valve fails, this can lead to pressure building up inside the water heater from the water pipes and sewage lines. If the water heater begins to overheat, this valve helps relieve it. If this fails, it could lead to the water heater exploding under the right circumstances. Annual maintenance and checks should check the TPR valve to ensure it’s not capped off, blocked, or have any other issues that could lead to an explosion.

Loss of Water Pressure

A loss of water pressure causes water throughout your home to act oddly. For your water heater, the TPR valve may open and begin to release excess pressure if there’s too much water pressure in your lines leading to the tank. In extreme cases, this can cause your water heater to begin leaking as it seeks to regulate the pressure inside. If your home suffers from water pressure loss, consider an expansion or storage tank to help control it and prevent water damage.

Water Heater is Old

As your water heater ages, loose parts, nuts, bolts, and more may cause issues that lead to it not heating. If you see leaking, however small, it may be as simple as tightening parts of it up to ensure it doesn’t continue. If you suspect your water heater’s age is at fault for heating issues or see leaking when it doesn’t heat, it’s time to consider replacing the unit.

Basic Troubleshooting Steps for a Hot Water Heater Not Heating

If you’re experiencing issues with your hot water heater not heating, you can try a few steps before contacting A.B. May:

  1. Check for any gas or electric issues in your area. This could be as simple as calling the gas or electric company to ask questions.
    1. For a gas water heater, check the pilot light and see if it’s lit; attempt to re-light it if you are comfortable with doing it.
    2. For an electric water heater, check to see if the fuse has blown in your breaker box. If it has, replace it, flip it, and see if that solves the issue.
  2. Test out every faucet and shower in your home, is it the whole home having issues with hot water, or is it localized to one part of the house?
  3. Try resetting the unit if it has a panel to do so. Refer to the manufacturer’s guidelines for your specific unit on how to do this.
  4. Thoroughly inspect the water heater for signs of rust, loose parts, leaking, and other issues that might be causing it not to heat water.
    1. Look for any signs of water damage in the area your water heater is installed. Even if it’s not active water damage, it may have leaked in the past, contributing to the issue now.

Keep in mind these are not exhaustive troubleshooting steps. Anything could've gone wrong during the installation process or from overall usage.

For the best way to troubleshoot your electric or gas water heater when it doesn’t heat water, refer to the manual or call A.B. May for a home visit.

When Is It Time to Call a Water Heater Professional?

Don’t be afraid to say, “I don’t know what’s wrong with the water heater.” Not everybody understands how these units work or want to fix them on their own. If you’re not sure what’s wrong, contact A.B. May to schedule an appointment. From tankless water heaters to older tank-type water heaters, we can fix them all.

Our water heater experts will come to your home, figure out what the issue is, and recommend what steps to take next. This could be as simple as making a repair to replacing the entire unit. We can look at the warranty you have and see what can be repaired or replaced under it. Perhaps, we can even help install an energy-efficient upgrade to your home. No matter what, we will explain your options so you can choose the best one for you. Let us give you peace of mind and ensure your water heater is working for you and your family.