It’s finally happened — your tankless water heater has stopped working. Whether it’s been a few months or several years since you purchased it, you’re left with a broken appliance and cold water. Before you call a maintenance specialist, look at this list of the top 10 reasons why your tankless water heater may not function properly. Armed with this knowledge, you should be able to solve the problem without too much hassle.

1. The Water Heater Isn’t Getting Enough Power

If your tankless water heater isn’t getting enough power, it won’t be able to heat the water properly. Find out if the unit is plugged in, and confirm that the circuit breaker hasn’t tripped. If everything looks good on those fronts, you may need to call an electrician from Fusion Plumbing & Air to look at the wiring.

2. There Is a Leak in the Water Line

Tankless water heaters are designed to provide a constant hot water supply, and they are very energy efficient. However, they can sometimes develop problems. A major problem is a leak in the water line. This can happen if the connection between the water line and the heater is not tight enough.

As a result, water can leak out, causing the unit to lose pressure and eventually stop working. Another problem that can occur is a buildup of minerals in the unit. Over time, these minerals can clog the internal parts of the heater, preventing it from working properly. If you think your tankless water heater is not functioning properly, ask a professional to check it for leaks.

3. The Thermostat Isn’t Set High Enough

Most people think their water heaters are set to the perfect temperature, but this isn’t always the case. If the water heater isn’t functioning properly, it might be because the thermostat isn’t set high enough. The ideal temperature for a tankless water heater is between 140 and 150 degrees Fahrenheit.

If your thermostat is set lower than this, your heater may not be able to warm the water properly, resulting in lukewarm or cold water. A low thermostat setting can also cause your water heater to cycle on and off more frequently, thus shortening its lifespan. If you’re having trouble getting your tankless water heater to work properly, check the thermostat, and make sure it’s set to the correct temperature.

4. The Pilot Light Is Out

If the pilot light is out, the gas supply to the unit will be shut off, and it will be unable to heat water. Sometimes, the pilot light may go out because the gas line has been turned off. In other cases, the pilot light may go out because of a faulty thermostat or another issue with the water heater itself.

If you suspect the pilot light is out, check the gas line to make sure it’s turned on. You should also check the thermostat to see if it needs to be replaced.

5. Sediment Buildup on the Heat Exchanger

If you’ve noticed that your tankless water heater isn’t working as efficiently as it used to, there’s a good chance that sediment has built up on the heat exchanger. This can happen over time as mineral deposits accumulate in the unit.

When those sediments gather, it prevents the water from being heated properly, reducing the appliance’s overall efficiency. If you suspect that sediment is the problem, it’s important to have a qualified technician inspect your heater. They will be able to clean the heat exchanger and restore it to working order. In the meantime, you can try running a white vinegar solution through the unit regularly to help dissolve any buildup.

6. The Gas Supply Has Been Turned Off

If you have a tankless water heater, you know they are a great way to save space and energy. Several issues may come into play, but one is dominant: The gas supply has been turned off. This can happen if you forget to pay your bill or if there is a problem with the gas line. If this happens, your water heater will not be able to function properly.

In addition, the pilot light may go out, and you will need to relight it. Check the gas supply first if you have problems with your tankless water heater.

7. The Flow Rate Is Too Low

Your tankless water heater may not function properly because the flow rate is too low. That’s common when there is a blockage in the pipes or the heater. To fix this, you will need to clean the pipes and the heating elements.

Another reason the flow rate may be too low is that the temperature of the water is too low. You can turn up the thermostat. If these solutions don’t work, you may need to replace your tankless water heater.

8. The Exhaust Vent Is Blocked

This is another reason why your tankless water heater may not function properly. Exhaust vents are responsible for carrying combustion gases and water vapor outside your home. If these vents become blocked, your tankless water heater can cause several problems, including decreased efficiency and increased risk of fires.

Additionally, blockages can cause overheating that can damage the heater itself. If you suspect that your exhaust vent is blocked, it is important to have it inspected and cleaned by a professional. This helps you avoid serious consequences down the road.

9. Using the Wrong Tankless Water Heater for Your Needs

There are several different tankless water heaters to choose from, each with its benefits and drawbacks. You’ll likely run into problems if you’re not using the right type of heater for your needs.

If you have a large household and use a lot of hot water, you’ll need a more powerful heater than someone who lives alone and only uses hot water occasionally. Likewise, if you live in an area with hard water — like Tucson or Phoenix, AZ — you’ll need to choose a heater that can handle the extra mineral deposits. By selecting the right heater for your needs, you can help it function properly for years to come.

10. Something Is Wrong With the Gas Line or Electrical Wiring

There are a few possible explanations if your tankless water heater isn’t functioning properly. One is an issue with the gas line or electrical wiring. Another possibility is that the intake valve is blocked, preventing water from entering the appliance.

Alternatively, the problem could be with a clogged or blocked exhaust vent. Finally, it’s possible that the unit needs to be descaled. If you’re unsure what the problem is, it’s best to call a professional for help. With our experience and knowledge, we’ll be able to pinpoint the issue and get your water heater up and running again.

Tankless water heaters are a great appliance in your home, but like any other machine, they can break down. If you’re having problems with your tankless water heater, call us for help. At Fusion Plumbing & Air, we also offer heating and cooling solutions for residents of Tucson and Phoenix, AZ, so give us a call today!

Fusion Plumbing & Air

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