8 Signs Your Water Heater is Failing

Castlewood Plumbing • January 16, 2024
Electric water heater next to a circuit breaker, blue toolbox, and a lever.

Is your water heater acting up? If you're noticing inconsistent temperatures upon delivery and limited supply, it may be time to inspect your system. For many homeowners, knowing when your system is failing is difficult. Understanding how to spot the signs of system failure can help you prevent significant damage to your home. Additionally, the sooner you know your system is failing, the sooner you can begin preparing to replace or repair your water heater.

How Long Should Your Water Heater Last?

The longevity of your water heater is crucial to maintaining a steady supply of hot water. The lifespan of a water heater can vary significantly based on its make, model, and usage. However, on average, you can expect a water heater to last between 10 to 12 years.



Several other factors can influence this lifespan, including:


  • Quality of the Water Heater: Investing in professional-grade water heaters and parts can significantly extend the life of your unit.
  • Water Quality: Hard water can take its toll on water heaters, causing sediment build-up, rust, and corrosion.
  • Pressure Levels: High pressure wears on the heater and other plumbing, while low pressure can indicate sediment in the heater.


Understanding these factors can help you take proactive measures to extend the lifespan of your water heater. Regular maintenance, using high-quality parts, ensuring good water quality, and monitoring pressure levels can help your heater function optimally for a long time.

Warning Signs Your Water Heater is Failing

Knowing how to spot the signs of a failing water heater can also save you from unexpected breakdowns and costly repairs. It's important to keep an eye out for the following warning signs:


  • Inconsistent Temperature: If your water's temperature isn't staying consistent, it could be a sign that your heater is beginning to fail. This inconsistency can be particularly noticeable during winter when the external temperature drops.
  • Running Out of Hot Water: Are you frequently finding yourself in a cold shower? This could be due to a sediment problem in your heater, indicating that it's on its last leg.
  • Leaking: A leaking heater tank often means it has rusted through – a clear sign of a failing water heater.
  • Noises: Unusual noises coming from your heater are typically caused by sediment build-up at the bottom of the heater. This should not be ignored.
  • Discolored or Rusty Water: Discolored or rusty water indicates that the anode rod in your heater is failing.
  • Smelly Water: If your water has a rotten egg smell, it's time to call a professional.
  • Higher than Normal Energy Bills: A failing heater often has to work harder, resulting in higher energy bills.
  • Excessive Repairs: If your heater requires frequent repairs, replacing it might be more cost-effective.



Any of these signs could indicate that your heater is not functioning as efficiently as it should, or worse, it's nearing the end of its lifespan. Ignoring these symptoms could lead to the complete failure of your water heater, leaving you without hot water when you need it most. Preventative maintenance is always better than dealing with a crisis, so if your system appears to be in good condition, consider implementing a maintenance routine if you’re not doing so already.

What to Do If You Notice Any of These Signs

At Castlewood Plumbing, we're always available to help our customers ensure their water heaters are working efficiently and safely. If you find yourself dealing with any of these issues we’ve covered, it may be time to contact a licensed and knowledgeable plumbing professional. Any of our experienced technicians at Castlewood Plumbing can examine your system and guide you through the best options to solve your water heater issues quickly and affordably. While we are on-site, a member of our team can also test your water quality. Many homeowners are shocked to learn that many of their plumbing problems stem from hard or poor-quality water.



Don't wait until it's too late; call 636-394-6737 to get your water heater checked today! Also, ask one of our team members about how to save an immediate 10% off your repair bills.

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