Similar to hissing, sizzling often indicates water dripping onto a hot component, usually the burner assembly in a gas water heater. This could be from a leaky temperature and pressure (T&P) relief valve, a loose pipe fitting, or even condensation if the flue isn't venting properly.
7 Warning Signs Your Water Heater Could Be About to Explode
Your heater likely makes a low humming sound throughout its operation. Heaters need professional attention if the humming becomes noticeably louder or changes to a buzzing noise. Loud humming or buzzing can indicate loose wiring, a malfunctioning transformer, or a failing capacitor.
Whooshing Noise – Likely Defrost Mode: In cold weather, your heat pump will periodically go into defrost mode to melt off frost buildup. When it switches, the reversing valve changes flow and you might hear a loud whoosh or swoosh of refrigerant.
Whistling or Hissing Sounds If your gas heater produces a whistling or hissing sound, it could be due to a problem with air circulation. A clogged or dirty air filter may restrict airflow, causing the sound. Replacing or cleaning the air filter is a simple fix that can restore proper airflow and eliminate the noise.
Common signs of a carbon monoxide leak include: Yellow or flickering furnace flame instead of blue. Soot or staining around vents or appliances. Unusual condensation on windows or cold surfaces.
If you smell a sulfur or rotten-egg-like odor, you could have a gas leak. Natural gas is naturally colorless and odorless. We add an odorant called mercaptan to natural gas, which gives it a distinctive smell. In some cases, you can also identify natural gas by sight or sound.
Know the Signs of a Gas Leak: Smell: Natural gas is odorless, so a harmless chemical called Mercaptan is added to give it a distinct smell — like rotten eggs or sulfur. Sound: Hissing or roaring noises can signal a leak.
5 Warning Signs It's Time for Furnace Replacement
Most heat pumps should complete about two to three cycles per hour, with ten to twenty minutes of downtime between each cycle. If you notice your system cycling too frequently or not enough, it could indicate an underlying issue that needs attention.
Here are key signs that indicate your heater core may be failing:
A malfunctioning heater can cause several different sounds, so call our experts as soon as you notice a squealing, banging, or rattling HVAC system.
Portable kerosene and unvented gas heaters release combustion products directly into your home. Overusing the heater or using an oversized heater can result in elevated levels of carbon monoxide or nitrogen dioxide fumes in the air.
Yes — water heaters can explode, but it's extremely rare and always preventable with regular maintenance. When it happens, it's not a fiery movie-style blast — it's pressure. Too much heat and trapped steam can turn a 50-gallon tank into a steel rocket.
Water Heater Lifespan
If your tank water heater is more than 10 years old, it may be time to consider replacing it. With proper maintenance, a tank water heater tank should last six to 12 years. A tankless water heater can last for more than 20 years. Check your water heater's warranty for the most accurate timelines.
Electric vs. Gas Safety Limits: With electric water heaters, minor external leaks may allow brief continued use, provided water isn't contacting any electrical components. For gas heaters, any gas smell or pilot light issues demand immediate shutdown and professional assessment.
The reality is that it's usually not a good idea to simply keep a heat pump operating all through the night while you're asleep. Instead, you should make sure that you have a programmable thermostat and set it to have it lower the indoor temperatures by 8° to 10°F when people are asleep.
If you're not sure how long it takes, try turning the heating on about 30 minutes before you need it. You should turn it off 30 minutes before you'll stop needing it. You might need to turn on your heating earlier if your home takes longer to reach a comfortable temperature.
A typical furnace runs for approximately 10 to 15 minutes per cycle, cycling three to eight times per hour. A short cycling system runs for less than five minutes, then quickly restarts, often cycling much more frequently. This pattern prevents efficient heating and creates massive strain on your equipment.
Signs that your furnace needs some degree of service can include the age of the unit, unusual or loud sounds coming from it, a lingering odor, and the furnace's efficiency.
The Average Furnace Lifespan
A well-maintained furnace can last at least 15 to 20 years, but completing annual maintenance and being diligent with furnace repairs can extend its life even longer.
Symptoms of Heater Sickness
Hissing or Whistling Sounds: Gas escaping a pipe under pressure often creates a hissing or whistling sound. The intensity depends on the size of the leak. Larger leaks might even produce a roaring sound. If you hear this, get out and don't hesitate!
If you notice any of the following symptoms, they could be caused by carbon monoxide leaking from your gas heater.
A rotten egg or sulfur smell, hissing sound, bubbling water, clouds of vapor, frozen ground when it's warm, or an area of dead plants or grass can all be signs of a gas leak.