Plumbing, Water Heaters

Avoiding a Water Heater Fire: Tips for Ensuring Safety at Home

Your water heater is essential to your daily life. The very idea of going without hot showers or being unable to use your dishwasher can seem daunting. Yet, like any other appliance, a concern tends to linger – the risk of a water heater fire. How can you minimize this risk while still enjoying the benefits of your water heater?

A water heater can cause a fire, but the risk is actually quite low. You significantly reduce the fire risk when you take the right steps with regular maintenance and safety precautions. And remember, don’t even think about storing flammable materials or liquids anywhere near a gas water heater.

It’s essential to understand that there are nuances and differences between various types of water heaters regarding fire safety. So, let’s delve into those differences and discuss the safety measures you can put in place right now to keep your family and home safe from a potential water heater fire.

Water Heater Fire

Understanding Fire Hazards: Gas vs. Electric Water Heaters

You may be asking: are there differences in fire safety between gas and electric water heaters? Both types of heaters may appear similar – they heat water using their respective energy sources and then release it into your home’s plumbing system. However, when it comes to fire safety, they’re not created equal. Gas water heaters have a significantly higher risk of causing a fire than their electric counterparts.

Why is this? One major reason is the type of energy they use: natural or propane gas in gas heaters versus electricity in electric heaters. Consequently, gas heaters can leak flammable vapors, while electric heaters are more susceptible to electrical fires.

Imagine your gas water heater starts leaking flammable vapors. The gas can accumulate around the heater or other nearby electrical appliances if this goes undetected. This vapor can trigger an explosion if it contacts the heater’s ignition flame or electricity.

Now, look at the brighter side – newer gas water heaters have a significantly lower risk of vapor-caused explosions. Why? These new models have sealed bottoms to guard the ignition flame from lurking gas. This safety feature is often missing in many older water heaters, making them more prone to explosions if a gas leak occurs.

In contrast, electric water heaters have a lower fire risk due to their non-reliance on combustible gas. Even if another appliance leaks gas near your electric heater, there’s no ignition flame to interact with the gas. Therefore, if fire safety is your primary concern, an electric heater might be the perfect fit for you.

The Fire Risk of Tankless Water Heaters: A Comparison

You’ve been caught up in the ongoing debate: which is better, tank or tankless water heaters? You’ve heard all about the initial costs, maintenance expenses, lifespan, and hot water supply of both types. But what about the fire risk?

Tankless water heaters can catch fire, but the risk is quite low. They only ignite and heat water when needed, reducing the overall risk. Most fire hazards in these heaters arise from potential gas leaks. Any electrical sparks near these leaks could ignite a fire or cause an explosion.

But don’t let this alarm you. Tankless water heaters have built-in safety features that shut them down if they detect a problem. If you suddenly find yourself without hot water and hear an unexpected beeping from your heater, there’s likely an error you’ll need to address.

Some tankless heaters have an expansion tank that can lead to pressure build-up, so it’s not all clear sailing. However, when comparing fire risks, tank heaters pose a greater hazard than tankless ones, mainly due to the water pressure accumulating in tank systems.

Let’s paint a picture: your tank heater is busy heating water and expands as the water warms, increasing pressure inside the tank. If not released, this pressure can become overwhelming and cause an explosion.

Although it sounds daunting, tank explosions are infrequent thanks to several safety measures in place. One is the temperature and pressure relief valve (T&P Valve) that releases water when the pressure reaches a dangerous point. This action effectively decreases the water volume and pressure inside the tank.

Another safety measure is the automatic heating shutoff mechanism. This feature kicks in when the pressure levels climb too high, stopping the heating process and curbing pressure escalation. These mechanisms are more common in newer models, so an older heater might only have the T&P Valve to protect you.

Since tankless heaters don’t have a tank, they bypass the risk of a pressure-induced explosion. But remember, safety is never absolute – tankless gas heaters can still emit combustible vapors, and that’s a fire hazard you’ll want to watch out for.

Staying Safe: Precautions with Water Heaters

You might feel slightly anxious after reading about explosive vapors and tank explosions. But don’t worry; you can put multiple safety measures in place to minimize the risk of a water heater fire or explosion. By addressing each of these points systematically, you can bring your risk down to a minimum.

Annual Maintenance Check

Start by scheduling a professional plumber to inspect your water heater once a year. While self-inspection is better than no action, a professional will be better equipped to spot potential issues you might overlook.

Regular Testing of T&P Valve

If you own a tank heater, check your T&P valve every few months to verify it’s working correctly. If you need guidance, here are simple steps to follow:

  1. Identify the T&P valve. If unsure, refer to our previous article, Leaky Water Heater Pressure Relief Valve: DIY Guide w/Pics.
  2. Wear closed-toe shoes to protect yourself from potentially scalding water.
  3. Place a bucket underneath the T&P valve’s discharge tube.
  4. Lift the valve switch, hold it for roughly five seconds, and then release.
  5. If water emerges from the discharge tube, your T&P valve works fine. If not, or if there’s a leak from the valve, you should contact a plumber immediately.

Inspect Your Anode Rod Every Two Years

Tank water heaters, usually made of steel, risk rusting over time. They’re equipped with an anode rod to prevent this corrosion. Also known as a ‘sacrificial’ rod, it sacrifices itself to protect your tank from rusting. Regular inspections will ensure it’s doing its job. If it corrodes completely, the water will rust the inner tank, which could lead to an explosion.

Lower Your Water Temperature

Higher water temperature can lead to increased pressure inside your tank. If your T&P valve is malfunctioning, reducing the water temperature can provide temporary relief.

Clear Flammable Substances from Your Water Heater Room

This one is particularly relevant if you have a gas water heater. Any flammable substances in the same room as your heater should be removed immediately. Common items to look out for include:

  • Paint and gasoline canisters
  • Cardboard boxes
  • Stacks of paper or fabric
  • Old wooden furniture

Ensure Correct Venting

Proper ventilation is crucial for gas heaters, both tank and tankless models. Any vent installation or design errors can cause a dangerous gas leak, leading to fire risks and potential carbon monoxide poisoning.

Leave Installation and Repairs to Professionals

While the DIY route might save some money, water heater repairs should be left to the experts. Any improper repairs can lead to serious consequences, so it’s best to call a professional plumber whenever you spot an issue with your water heater.

Do You Need a Licensed Plumber?

Get FREE quotes from licensed Plumbers in your area today. Whether you need a new water heater, a sink repair, or a toilet fixed, We Can Help! All Plumbers are screened, licensed, and insured.

Get a FREE Quote Today
We earn a commission if you purchase at no additional cost to you.

Hubert Miles | Licensed Home Inspector, CMI, CPI

Hubert Miles is a licensed home inspector (RBI# 2556) with more than two decades of experience in inspection and construction. Since 2008, he has been serving South Carolina through his company, Patriot Home Inspections LLC. As a Certified Master Inspector, Hubert is dedicated to providing his expertise in home inspections, repairs, maintenance, and DIY projects.