What to Do if Your Water Heater is Taking Too Long to Heat Your Water
There’s nothing worse than turning on your shower expecting warm water and waiting… and waiting… only to get a blast of lukewarm or cold water. Slow-heating water heaters are a common frustration for many homeowners in Durham, NC, and the surrounding areas. Whether you have a traditional tank-style heater or a newer tankless model, long wait times can signal an underlying issue that needs attention.
At Acme Plumbing Co., we’ve worked with water heaters of every size, age, and brand, and we know that slow heating isn’t just an inconvenience, it can be a sign that your unit needs maintenance, repair, or even replacement. Let’s break down what causes your water heater to take too long to heat water, what you can do about it, and when to call in a professional.
Check the Age and Type of Your Water Heater
The first step is understanding what kind of water heater you have and how old it is.
Traditional tank water heaters store and heat a set amount of water, usually between 30 and 80 gallons, using either gas burners or electric elements. Once that water is used up, the tank must refill and reheat before it’s ready again. That reheating process can take anywhere from 30 minutes to an hour, depending on the unit’s size, condition, and temperature setting.
Tankless water heaters, by contrast, heat water instantly as it passes through the system. If a tankless model is taking too long, it could indicate a problem with the flow sensor, heating element, or even a sizing issue where the unit can’t handle your home’s demand.
If your system is more than 10 years old, slow heating may be the first sign that it’s losing efficiency due to wear and mineral buildup. Water heaters don’t last forever. Most traditional tanks last about 8 to 12 years, while tankless systems can last up to 20 years with proper maintenance.
Inspect for Sediment Buildup
Durham’s water supply is considered “moderately hard,” which means it contains minerals like calcium and magnesium. Over time, these minerals settle at the bottom of your water heater’s tank, forming sediment that acts like insulation between the heating element and the water.
As the layer of sediment thickens, your heater must work harder and longer to warm the water. You might also hear rumbling or popping sounds as trapped air bubbles rise through the sediment layer.
The fix? Flushing your water heater once or twice a year removes that buildup and helps restore its efficiency. It’s a simple maintenance task that can save you from bigger problems later, like overheating, leaks, or reduced lifespan.
At Acme Plumbing Co., we perform professional tank flushes that safely clear sediment without damaging the heating elements or tank lining.
Adjust the Thermostat Setting
Sometimes, the issue is as simple as the thermostat being set too low. Water heaters are typically preset between 120°F and 140°F, but if yours is closer to the lower end, it may take longer to reach a comfortable temperature.
Try turning the thermostat up by 5 to 10 degrees and give the system about an hour to recover. Then, test your hot water again.
If you have young children or elderly family members at home, be cautious about increasing the temperature too much, as water above 125°F can cause scalding. A professional plumber can help you find the safest and most efficient setting for your household.
Check for Long Pipe Runs or Poor Insulation
In some homes, especially larger or multi-story ones, the hot water has to travel through long stretches of pipe before reaching your faucet or shower. During that journey, the water cools down, which makes it feel like your heater is taking too long, even though the issue is actually heat loss in the pipes.
One solution is to insulate your hot water pipes, which helps maintain water temperature as it travels through your plumbing system. Another option is installing a hot water recirculation system, which keeps hot water circulating through the lines so it’s ready the moment you turn on the tap.
Both options can dramatically reduce wait time and improve comfort, especially in homes with bathrooms or kitchens located far from the water heater.
Test the Dip Tube (for Tank Water Heaters)
Inside a traditional tank water heater, there’s a small but crucial component called the dip tube. It directs incoming cold water to the bottom of the tank, where it’s heated.
If the dip tube breaks or cracks, the cold water may mix with hot water near the top instead of staying separated. This results in lukewarm water at your taps and slower heating recovery times.
Replacing a dip tube is an inexpensive repair, but it requires draining the tank and accessing internal parts, so it’s best handled by a licensed plumber.
Evaluate the Heating Elements or Gas Burner
For electric water heaters, slow heating often points to a failing heating element. Most units have two elements, one near the top and one at the bottom. If one burns out, the heater can only warm half the tank efficiently, leading to longer recovery times and inconsistent temperatures.
For gas models, the issue might be with the gas burner or pilot assembly. Dust, debris, or rust buildup can reduce the flame’s size and efficiency, making it harder to heat water quickly.
Both situations can be tested and fixed by a professional plumber. Our team at Acme Plumbing Co. can check your electrical elements or burner assembly, clean or replace parts, and ensure your system operates safely and efficiently.
Consider the Size and Demand of Your System
If your household has grown or you’ve added new water-heavy appliances (like a soaking tub or dishwasher), your existing water heater may simply be undersized for your needs.
Each time someone showers, runs the washing machine, or does dishes, hot water is drawn from the same tank. Once it’s empty, you’ll need to wait for it to reheat.
The rule of thumb is to have a tank that holds roughly 10–15 gallons per person in your home. For tankless systems, it’s about matching the flow rate (gallons per minute) to your peak water usage.
If your water heater struggles to keep up even after maintenance, upgrading to a larger or more efficient system can make a huge difference.
Check for External Plumbing Issues
Sometimes, the water heater isn’t the problem at all, it’s the plumbing. Leaky faucets, dripping shower valves, or even small pipe leaks can draw hot water out of the system and reduce what’s available for use.
A slow-heating problem might also be caused by partially clogged hot water lines. Mineral buildup or corrosion inside pipes can restrict water flow and cause temperature fluctuations.
Our team uses advanced diagnostic tools, including thermal imaging and camera inspections, to pinpoint any hidden plumbing issues that affect your water heater’s performance.
Schedule Routine Water Heater Maintenance
Even the best water heater needs regular maintenance to stay efficient. A professional tune-up includes:
- Flushing sediment from the tank
- Testing thermostat accuracy
- Checking heating elements or gas burners
- Inspecting the pressure relief valve
- Examining anode rods for corrosion
These steps help your water heater run faster, safer, and longer. Regular maintenance also ensures you catch small issues, like a failing thermostat or corroded connector, before they turn into major problems.
Know When It’s Time to Replace Your Water Heater
If your water heater is more than a decade old and has started taking longer to heat water despite regular maintenance, it might be nearing the end of its lifespan.
Modern water heaters, especially tankless or hybrid models, offer better performance and faster recovery times. They also save energy by heating water more efficiently.
Replacing an aging water heater can reduce your utility bills and restore the convenience of instant hot water in your home.
Common Water Heater Complaints We Solve in Durham, NC
Durham homeowners often face:
- Long waits for hot water in upstairs bathrooms
- Lukewarm showers after one family member uses hot water
- Strange noises from the tank due to sediment
- Inconsistent temperature during multiple uses
- Slow recovery after laundry or dishwasher cycles
At Acme Plumbing Co., our experts quickly identify whether the issue lies in the heater, pipes, or thermostat and fix it efficiently.
FAQs About Slow Water Heaters
1. How long should it take for a water heater to reheat water?
A traditional 40-gallon gas water heater usually takes about 30–40 minutes to reheat. Electric models can take up to an hour.
2. What temperature should my water heater be set to?
Most homeowners find 120°F ideal, it’s hot enough for daily use while still energy efficient and safe.
3. Can sediment buildup cause slow heating?
Yes. Sediment acts as an insulator between the heat source and water, forcing the unit to work harder and heat slower.
4. Should I flush my water heater myself?
You can, but professional flushing ensures all sediment is removed safely and that components are inspected for wear or corrosion.
5. How often should I service my water heater?
Once a year is ideal to maintain performance, extend lifespan, and prevent heating delays or breakdowns.
Tired of waiting for hot water? Call Acme Plumbing Co. at (919) 688-1348 for expert water heater repair and maintenance in Durham, NC.
