If you've noticed strange noises coming from your water heater, you're not alone. Many homeowners experience sounds like popping, rumbling, hissing, or banging from their water heaters. While some noises are harmless, others may indicate an issue that needs attention. Understanding what causes these sounds can help you determine whether a simple fix is needed or if it's time to call a professional.

Water Heater Noise #1: Popping or Rumbling

One of the most common water heater noises is a popping or rumbling sound. This usually occurs due to sediment buildup at the bottom of the tank. Over time, minerals from hard water settle and form a layer, trapping water beneath it. When the water heats up, it turns to steam and forces its way through the sediment, creating a popping or rumbling noise.

Solution: Flushing your water heater regularly can help remove sediment and improve efficiency. If you haven't had your water heater serviced in a while, it may be time to schedule a professional flush and inspection.

Water Heater Noise #2: Hissing or Sizzling

A hissing or sizzling noise often indicates a leak, particularly if you have a gas water heater. When water drips onto the burner or other hot components, it can create these sounds. Electric water heaters may also hiss if sediment buildup causes the heating element to be partially covered in water and air.

Solution: Check for visible leaks around the tank, valves, or fittings. If you suspect a leak but can’t locate it, a professional plumber can diagnose the issue and recommend repairs or a replacement if necessary.

Water Heater Noise #3: Banging or Knocking (Water Hammer)

If you hear loud banging or knocking noises, this could be due to a phenomenon called water hammer. This occurs when water suddenly stops or changes direction in the pipes, causing a shockwave that results in loud noises. This can happen when valves shut off quickly or if there's high water pressure.

Solution: Installing a water hammer arrestor can absorb the impact of sudden water movement, reducing noise and preventing potential pipe damage. If high water pressure is the issue, a pressure-reducing valve may help.

Water Heater Noise #4: Ticking or Tapping

Ticking or tapping noises often stem from the expansion and contraction of the water heater’s metal components as they heat up and cool down. This is typically harmless and common in many units.

Solution: If the noise is excessive, you may want to check for loose pipe straps or other metal components that could be shifting. Wrapping pipes with insulation can sometimes reduce noise as well.

Water Heater Noise #5: Crackling 

For gas water heaters, a crackling sound can occur when condensation drips onto the burner and sizzles as it evaporates. While this is usually not a major concern, excessive moisture inside the unit could lead to rust or efficiency issues.

Solution: If you notice excessive moisture around the base of your water heater, it’s a good idea to have a technician inspect it to rule out leaks or venting issues.

When to Call a Professional for a Noisy Water Heater

While some water heater noises can be resolved with simple maintenance, others may signal a more serious problem. If your water heater is making loud, persistent noises or showing signs of leaks, reduced efficiency, or inconsistent hot water, it’s best to call a professional for an inspection.

At Bovio Rubino Service, we offer expert water heater maintenance, repairs, and replacements in South Jersey to keep your home running efficiently. Contact us today to schedule an inspection and ensure your water heater is working safely and effectively!