All tank-type water heaters have a certain recovery time, which is how long it takes for the unit to fully reheat once all of the stored hot water has been used. The exact length of a water heater’s recovery time depends mostly on how many gallons its tank holds. The fuel source also plays a role, as gas units typically heat quite a bit quicker than electric units. An 80-gallon gas water heater should reheat in around an hour, while the recovery time for electric units could be as much as two hours. If your water heater starts taking much longer to reheat, here are the possible causes and how to fix them.
1. Sediment Buildup
Your water supply contains quite a bit of dissolved minerals like calcium and magnesium, especially if you live in an area with hard water. When the water is heated, some of these minerals solidify into sediment that settles to the bottom of the tank. This is why all tank water heaters should be drained and flushed at least once a year. This helps remove the sediment so that it doesn’t interfere with the unit’s ability to heat or damage its heating element.
Sediment buildup is typically a bigger problem for gas water heaters since most of the heat comes directly from the gas burner underneath the unit’s tank. A thick layer of sediment will basically act like a blanket of insulation and prevent much of the heat from the burner from being transferred to the water. As a result, the recovery time will be far longer since the sediment absorbs so much of the heat. As the sediment absorbs heat, it can also lead to hot spots developing that can start to weaken the tank, potentially to the point where the unit starts to leak. This is another reason why regular flushing is so important.
Electric water heaters typically have one electric heating element near the bottom of the tank and a second element in the upper portion. If the sediment builds up to where it comes into contact with the lower heating element, it will insulate the element and again prevent much of the heat from being transferred to the water. Sediment can also potentially damage the lower heating element and cause it to wear out.
Flushing a water heater is typically something you can do on your own. However, we’d still recommend having a professional plumber do it for you since they can also inspect and maintain all of the other components at the same time to help prevent long recovery times and other issues.
2. Dirty Gas Burner
Having your water heater professionally maintained every year is important for several reasons. One essential part of maintaining a gas water heater is cleaning the unit’s burner, as it will generally always become coated in dirt and grime over time. All the dirt has the potential to clog some of the burner ports, which means the burner will produce much less heat and the recovery time will be much longer.
The burners also usually won’t work properly when overly dirty, and this can lead to the gas not fully combusting. Incomplete combustion produces weaker yellow or orange flames that give off far less heat than the strong blue flame you get when the gas fully combusts. Again, this will lead to a longer recovery time since the burner isn’t producing nearly as much heat as it should due to incomplete combustion.
3. Worn-Out Electric Heating Element
If you have an electric water heater that suddenly starts heating much more slowly, we’d recommend having it inspected. There’s a good chance that one of the heating elements is worn out or starting to fail. A failing or worn-out heating element won’t just lead to a longer recovery time; it can also greatly increase the amount of electricity the unit uses since it will always need to run for much longer than it would when working properly. Replacing a worn-out heating element is a fairly simple fix. However, if your water heater is more than eight to 10 years old, we’d typically recommend opting to install a new unit instead since it likely won’t last that much longer even with a new heating element.
4. Broken Dip Tube
All tank water heaters are designed so that hot water is drawn out of the top of the tank and the incoming cold water goes directly to the very bottom of the tank through something known as a dip tube. This is important for a few reasons. For starters, the dip tube helps to prevent the incoming cold water from mixing and lowering the temperature of the hot water in the upper portion of the tank. If the cold water didn’t flow directly to the bottom of the tank, the recovery time would always be longer and the unit would use more energy. Your water would also never be as hot except for times when it has been more than an hour or two since you last used any hot water.
While this issue is somewhat rare, the dip tube can potentially crack or break. This will lead to the incoming cold water quickly lowering the overall temperature inside the tank and the unit taking much longer to heat. Luckily, a broken dip tube is another issue that’s fairly inexpensive to fix.
5. Failing Water Heater
There’s also a high chance that your water heater is taking longer to heat simply because it’s old and starting to wear out. Even with regular maintenance, the heating efficiency of most water heaters will decrease the older the unit gets. Most tank water heaters will only last for around 10 years. If your unit is approaching this age and taking longer to reheat, it’s probably time to start thinking about replacing it. Not only will a new unit heat more quickly, but it’s almost guaranteed to use less energy since new water heaters are generally much more energy-efficient than older units.
When it does come time to replace your water heater, you may want to consider upgrading to a tankless unit instead. One major advantage of opting for a tankless water heater is that you’ll never need to wait for the unit to reheat. It always heats on demand, which means you’ll never run out of hot water.
The fact that tankless units don’t store hot water and thus don’t need to continually reheat means that they also typically use quite a bit less energy than tank water heaters. Depending on how much hot water you typically use in a day, a tankless unit could reduce your energy costs by anywhere between 10% and 40%.
If your water heater is taking too long to heat, the team at Hope Plumbing can determine what the reason is and whether it’s better to repair the unit or install a new one. We work on all brands and types of water heaters. We also offer a full range of other plumbing services for customers throughout the Indianapolis area, including drain cleaning, leak detection, sewer repair, and more. Contact us today if you have any questions or to schedule a service call.