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Learning CenterContinuous hot water is just one of the many benefits your tankless water heater can provide, yet it is prone to some problems. Tankless water heaters can be beneficial for your home, but they can also have some issues that aren’t uncommon. If you find yourself dealing with common tankless water heater problems, get ready to learn about their possible solutions.
From Noritz to Navien, we at Monkey Wrench have almost two decades of experience working with all tankless water heater models. Despite their many benefits, we’ve seen how tankless water heaters can experience common issues. With specialized training from the top brands in the industry, we’ve been able to service and repair hundreds of tankless water heaters across Los Angeles and the surrounding areas.
From our experience, here are the top tankless water heater problems.
- Lack of hot water
- Cold water sandwich
- Leaking water
- Poor water flow
- Mineral buildup
As common as these issues are out in the field, there are multiple possible fixes so you can return to enjoying the hot water provided by your tankless water heater. With all of this information, you’ll gain a better understanding of why these issues occur and learn about possible solutions should you encounter them.
Let’s dive in!
What Are the Top Tankless Water Heater Issues and Their Fixes?
Tankless water heaters provide hot water without storing and keeping hot water on standby in a tank like conventional water heaters. Still, they’re prone to sometimes run into issues that will require immediate attention so your home can have hot water again.
Before we dive into each issue, we should disclose that a certified professional should address any problem your tankless water heater is experiencing. With their available tools and resources, a technician can properly diagnose and repair your tankless water heater.
In the next section, we’ll look at the common causes and solutions for a lack of hot water from your tankless water heater.
1. Lack of Hot Water
Sometimes, a tankless water heater may fail to provide hot water to your home. The symptoms of a lack of hot water are noticeable when waiting for hot water to come out of a faucet.
There are several reasons why your tankless water heater is failing to provide your home with hot water, such as.
- No flame: For gas-powered tankless water heaters, the flame assembly and igniter create a spark, while gas is supplied to create a flame that heats water. For electric tankless water heaters, water is heated through electric currents. If there’s a problem with any of the parts that help produce hot water, your tankless water heater will not have hot water available.
- No gas: If no gas is supplied to your tankless water heater, it will not have fuel to create a flame for water heating.
These are some of the common causes of lack of hot water. Now, we’ll review possible solutions.
Lack of Hot Water Solutions
If you notice a lack of hot water from your tankless water heater, the first thing to do is book an appointment with a technician. After shutting off your tankless water heater and water line access, a technician can take apart a tankless water heater to see what the cause of the lack of hot water is.
If there are any failing parts, the technician can replace them and even submit a warranty to claim to see if the manufacturer covers them. The entire repair process can take a few hours, but once it’s completed, you should have hot water again.
The next issue occurs more commonly than homeowners think, but like any tankless water heater problem, it has a solution.
2. Cold Water Sandwich
Have you ever turned on the shower and got hot water only to get a burst of cold water before getting hot water again? Then, you’ve experienced what is referred to as a cold water sandwich.
Leftover hot water from a tankless water heater can remain in your home’s water pipes until there’s a need for hot water again. When a hot water faucet is turned on, the leftover hot water is dispersed before cooled-down water comes out. During this time, your tankless water heater is already heating new water to distribute.
It’s possible to experience a short delay in hot water when dealing with hot water sandwiches. As annoying as this issue can be, it doesn’t necessarily mean there’s an issue with your tankless water heater, but a solution is available.
Solutions for Cold Water Sandwich
Installing a recirculating pump is the best way to reduce and eliminate the cold sandwich effect from your tankless water heater. A recirculation pump helps circulate hot water throughout your home’s pipes so it is readily available.
With a recirculation pump, you can also reduce the time it takes for hot water to arrive from your tankless water heater to your desired hot water fixture. If you desire a recirculation pump line for your home, you’ll need to schedule an appointment for a technician to come and install one in your home.
Increased hot water delivery times sound ideal, but they can be pointless if your tankless water heater is experiencing a leak.
3. Tankless Water Heater Leaks
One of the most common problems homeowners face with their tankless water heaters is leaks. A leaking tankless water heater will have visible water near it. There are many reasons why your tankless water heater is leaking, such as.
- High water pressure
- Loose parts
- Defective parts
- Poorly installed
- Corroded parts
- Hard Water
Older tankless water heaters are prone to more problems, such as water leaks.
Another sign that your tankless water heater leaks is tied to high water bills. If you suspect or notice your tankless water heater leaking, it’s best to call and book an appointment with a technician immediately.
Solutions for Tankless Water Heater Leaks
Similar to some of the issues discussed in this article, a technician will first inspect the source of your tankless water heater leak and then find the appropriate repair. A simple repair may involve tightening a water inlet or outlet. On the other hand, a complete rebuild or replacement may be needed to stop the leak.
Once a technician takes the appropriate measures to stop and prevent the leak, you can continue to enjoy hot water. However, poor water flow can still occur, which is another issue you may face with your tankless water heater.
4. Poor Water Flow
Poor water flow with your tankless water heater can have different causes, but the most common is low water pressure. Blockages in your water pipes can make it difficult for water to flow out of your fixtures, like a showerhead, for example.
High hot water demands can also lead to poor water flow. Tankless water heaters come in different capacities to meet the hot water demands of homes depending on their size, number of bathrooms, and people living in them.
Poor water flow may occur if you use the shower while running the washing machine, dishwasher, and any other appliance that uses hot water. This can happen if your tankless water heater isn’t suited to handle such unexpectedly high hot water demands.
The poor water flow of tankless water heaters isn’t permanent, but there are solutions to this problem.
Tankless Water Heater Poor Water Flow Solutions
If you’re experiencing poor water flow, contact a technician for a diagnosis. If a clog is causing the problem, a technician has the right tools to clear it.
If everything is okay with your tankless water heater, then the technician can inspect the water pressure valve and ensure it’s in the correct position. The technician may also recommend a tankless water heater replacement with a suitable capacity to meet your home’s high hot water demands.
5. Limescale Buildup
Minerals from hard water are attracted to heat, so it’s common to see limescale buildup in your tankless water heater. The minerals responsible for causing limescale are calcium and magnesium, and the limescale it leaves behind is visible as a white, chalky-like substance.
Your tankless water heater will experience a drop in efficiency because limescale can build up on the heat exchanger, forcing the unit to use more energy to produce hot water. Limescale buildup can also lead to poor water flow, obstructing hot water from reaching a desired fixture. Sometimes, limescale buildup can cause your tankless water heater to overheat, leading to part failures and early breakdowns.
As scary as limescale buildup sounds, removing it and preventing it from happening again is possible.
Solutions for Limescale Buildup
A technician must first perform a tankless water heater flush to remove the limescale and prevent its effects from damaging your tankless water heater. This helps remove any of the minerals inside the unit that can be tricky to remove on your own.
Tankless water heater flush is part of annual maintenance that can help extend the life of your water heating unit.
Once the flush is completed, it is recommended that you install a water softener or Flow-Tech device. Water softeners remove the minerals that cause limescale entirely and can produce soft water, which has many benefits. A Flow-Tech device is a much smaller device that doesn’t remove limescale minerals but instead prevents them from sticking to your tankless water heater and the rest of your home’s water pipes.
Addressing Common Tankless Water Heater Problems
As tankless water heaters are becoming the go-to water heaters for newly constructed and older homes everywhere, it’s important to pay attention to the common issues that may arise. There’s a high chance your tankless water heater won’t face any of the problems discussed above. Still, now that you have a general idea of the common tankless water heater problems and their solutions, you can have peace of mind knowing they can be taken care of.
At Monkey Wrench, we’ve encountered all kinds of tankless water heater problems, from leaks to breakdowns. Thanks to specialized training and available resources, we’ve addressed and repaired hundreds of the issues related to tankless water heaters across Los Angeles and the surrounding areas.
If you have a tankless water heater issue, please contact us immediately using one of the buttons below. You can also book an appointment using the link for our online tankless water heater scheduler.
