Common Tankless Water Heater Issues

  1. San Diego Water Heater Repair
  2. Tankless Water Heater Repair
  3. Common tankless water heater issues

Tankless water heaters are a great way to save money on your energy bills, but they can come with their own set of problems. From strange noises coming from the unit to unusual odors, it can be difficult to know what the issue is and how to go about fixing it. In this article, we'll explore some of the most common tankless water heater issues and how to address them. Whether you're looking for a quick fix or a more in-depth repair, this article will provide you with the information you need to keep your tankless water heater running smoothly.

From understanding the basics of how a tankless water heater works to troubleshooting some of the most common problems, you'll be able to get your water heater back up and running in no time.


Leaks are one of the most common tankless water heater issues. They can be caused by a variety of reasons, including rust, worn gaskets, and inadequate insulation. If you notice any water pooling around your tankless water heater, it could be a sign of a leak. Fortunately, there are several things you can do before calling a repair technician.

First, check the pipes for any signs of rust or corrosion. This is particularly common in older models and can lead to leaks. If you find any rusty spots, you may need to replace the pipes or call a repair technician for help. Second, inspect the gasket for any signs of wear or tear.

If the gasket is cracked or worn out, it can lead to a leak. Replacing the gasket is usually an easy fix and can be done without professional help. Finally, make sure that the tankless water heater is properly insulated. Poor insulation can lead to condensation and cause your tankless water heater to leak.

If your insulation is inadequate, consider replacing it or calling a repair technician for help.

Thermostat Issues

One of the most common tankless water heater issues is thermostat problems. The thermostat is responsible for regulating the temperature of the water and if it malfunctions, it can cause a variety of problems. Common signs that there is a problem with the thermostat include water that is too hot or too cold, or water that doesn’t get hot at all. If you are experiencing any of these issues, the first thing to do is to check the thermostat settings.

Make sure the temperature is set to the desired level and that it is not set too low. If the thermostat settings are correct, then it’s possible that the thermostat itself has malfunctioned and needs to be replaced. Another common cause of thermostat issues is a buildup of sediment and scale in the tankless water heater. If this is the case, you may need to flush out the system and replace any clogged parts.

It’s also important to make sure that the unit is properly ventilated, as a lack of ventilation can cause the thermostat to malfunction. Finally, if you’re still having trouble with your tankless water heater’s thermostat, it may be time to call a repair technician. A qualified technician can accurately diagnose the issue and make any necessary repairs or replacements to ensure your tankless water heater is running properly.

Lack of Hot Water

Lack of hot water is one of the most common tankless water heater issues.

There are several potential causes, including low water pressure, a malfunctioning thermostat, or a failed heating element. Before you call a repair technician, there are a few things you can check to troubleshoot the issue.

Water Pressure

If your tankless water heater isn't producing enough hot water, the first thing to check is your water pressure. Low water pressure can prevent your tankless water heater from delivering the necessary amount of hot water. If you have a traditional tank-style water heater, you may have a pressure regulator attached to the main water line coming into your home.

If that's the case, you should check the pressure regulator and make sure it is set correctly. If it is set correctly, you may need to call a plumber to investigate further.


Your tankless water heater has an adjustable thermostat that allows you to control the temperature of the hot water. If it's set too low, it may not be producing enough hot water. You can check the thermostat by looking at the manufacturer's instructions for your specific model and make sure it's set correctly.

If it is set correctly, you may need to replace the thermostat.

Failed Heating Element

If your tankless water heater isn't producing enough hot water, it may be due to a malfunctioning heating element. This is often caused by limescale buildup on the heating element, which can prevent it from properly heating the water. You should inspect the heating element for signs of limescale buildup and clean it if necessary. If that doesn't solve the problem, you may need to replace the heating element. If you've checked all of these items and your tankless water heater is still not producing enough hot water, it's time to call a repair technician.

They will be able to diagnose and repair any underlying issues with your tankless water heater.

Strange Noises

Strange noises coming from your tankless water heater can be concerning. Thankfully, they are usually easy to diagnose and fix. Common causes of these noises include mineral build-up, loose components, and air in the line. To troubleshoot this issue, first check the inlet and outlet pipes for any mineral deposits and clean them if necessary.

Make sure all the components are properly secured and tighten them if needed. If the noise persists, there may be air trapped in the line, so try purging the unit to get rid of it. If the strange noises still don’t go away after attempting these fixes, it may be time to call a professional repair technician. They will be able to inspect the unit more thoroughly and pinpoint the source of the problem.

Professional technicians can also replace any parts that need to be replaced in order to get your tankless water heater back up and running smoothly.