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Troubleshooting Tankless Water Heater Problems

water heater

Installing a tankless water heater is an excellent investment to improve your home’s energy efficiency. It also streamlines energy consumption and maintenance budget. The heating device is durable and may last ten to twenty years if you maintain it properly. It uses less energy while ensuring that your home receives a steady hot water supply.

While there is no doubt that tankless water heaters are a great investment, they need proper attention and care to stay in tip-top shape. After all, these durable and energy-efficient devices have some unique problems of their own. You need to flush them regularly and complete a few preventative tasks.

While troubleshooting a tankless water heater’s issues can be difficult for most homeowners, there is no need to scratch your head and wonder where to start. Fortunately, your professional water heater repair service can help keep your heating unit working flawlessly. This extensive guide includes the most common problems your tankless water heater can face, as well as how you can fix them.

Let’s begin by understanding what a tankless water heater is and how it works.

Table of Contents

  • Tankless Water Heater- An Overview
  • Everything to Know about the Tankless Water Heater
    • » How it Works
  • Troubleshooting Tankless Water Heater Problems
    • » There’s No Ignition
    • » Flame Failure
    • » Burners Fail to Ignite
    • » Noisy Burner
    • » No Hot Water
    • » Winter Weather
    • » What Else!
  • Summing Up

Tankless Water Heater- An Overview

A tankless water heater, or instantaneous/demand-type water heater, provides hot water much faster than a normal heater. People consider it a better option because it doesn’t generate the standby energy loss typically associated with water heater storage, making it fantastic to save money.

If your home uses approximately 41 gallons of hot water, a tankless water heater can be 25 percent to 35 percent more energy-efficient than a traditional storage water heater. It is an excellent option for homes with higher water consumption.

The initial cost of this heating unit is remarkable in comparison to that of a traditional storage water heater. But, it typically lasts longer and has lower operating costs. The feature offsets a higher purchase value. Many tankless water heaters come with a life expectancy of twenty years. As most parts are easily replaceable, a single heating unit can last many years.

As mentioned above, a tankless water heater prevents standby heat loss in storage water heaters. Though a gas-fired tankless water heater tends to have a higher energy flow rate than electric heaters, they waste energy if they constantly burn pilot light.

Related Article: Everything to Know about the Tankless Water Heater

How it Works

Tankless Water Heater ServicesA tankless water heater heats water directly without using a storage tank. When you turn on the hot water tap, cold or regular water travels into the unit through a pipe. Either an electric element or gas burner heats the water.

A tankless heater, as a result, delivers a constant hot water supply. There is no need to wait to fill the storage tank with hot water. However, the output of a tankless water heater may limit the flow rate. This advanced heating unit provides a hot water supply at a rate of 3 to 5 gallons (15.5 liters) per minute.

The largest model of a gas-fired heating unit often fails to supply enough supply of hot water. It happens due to multiple uses of hot water appliances in a household. For instance, using dishwater and running a shower at the same time stretches a heating unit to its limit.

People often install more tankless water heaters for simultaneous demands and uses of hot water. Installing separate tankless water heaters for different appliances such as dishwashers, washing machines, etc., is a good idea to overcome the hot water shortage issue.

Some other applications of water heaters for different demands include;

  • Hot tub or remote bathroom
  • Booster for electronic appliances, such as clothes washers or dishwashers
  • solar water system booster

Gallegos Plumbing is the renowned name for water heater repair and installation services in Ventura County with years of experience assisting customers with all their tankless needs! Call us now at (805) 243-2622 to schedule an appointment for an affordable water heater and other plumbing services.

Troubleshooting Tankless Water Heater Problems

Sometimes your tankless water heater (gas) displays a “no ignition” sign or message. That means your unit is making attempts to light, but it can’t due to some reasons. The issue can be related to gas supply or venting. It may also happen;

  • If you use a heating unit that runs on propane, it may stop running due to a gas shortage. You need to check the fuel source.
  • If your heating unit’s fuel source is natural gas, make sure you check other appliances using the same fuel sources. If they are not working properly, the Gas Company may have shut off the gas.
  • You can also check the gas and water valves to check if they are open. The blocked valves can also cause a tankless water heater to not light.

If the problem remains the same after even taking the above-mentioned steps, it is best to contact a professional plumber. He will assess the situation, and if there is a significant problem, such as the need for replacements, he can guide you on how to address it.

Flame failure is another common problem you may face with a tankless water heater. When there is an issue with gas pressure, the heating unit may give you an error message, saying “flame failure.” Try to resolve the issue with easy fixes, including turning off the gas or emptying the propane tank, before switching to complicated solutions.

If you think the problem is not simple and you’re unable to resolve flame failure, call an experienced technician or professional to troubleshoot it. They will measure the pressure using the right tools and find the part in need of repair.

If a technical and electrical issue, a professional plumbing contractor, Gallegos Plumbing, can help fix your tankless water heater.

Low pressure of the gas may cause the following problems;

  • Gas regulators failure
  • Narrow gas line
  • Combustion issues
  • Venting Issues

Most gas tankless water heaters have burners to heat the water. When the cold water travels through the heating unit, the system transfers heat to the water. If the water remains cold, that means the burner didn’t ignite.
The problem can be like a closed gas valve or poor venting. You may troubleshoot the problem yourself, but it is ideal to contact a trained professional. We say this because many reasons can prevent your burner from lighting.

Some of the possible causes include;

  • Gas Flow Problem – Checking a pilot light is also essential to see if it remains lit or there is a pilot light or not. There can be other problems with gas pressure.Contacting a professional plumber near you is the right decision to find out the cause without wasting time.
  • Electrical Issue – If your tankless water heater trips the circuit breaker, you need to call a professional to identify and address the problem.
  • Flow Sensors Issue – Flow sensors indicate the tankless water heater to activate. If they start wearing out, the burner will not turn on.

Usually, a tankless water heater makes noises when it functions. But if it makes a loud rumbling sound that you have never heard before, it is a signal that something is wrong.

Some possible causes can be;

  • Loose debris in the fan
  • Burner has stopped working, or flame has changed the color
  • The burner flame is not stable due to improper venting, insufficient combustion, and low gas pressure

This might bizarre to you but “no hot water” is one of the common problems with tankless water heating units. Water, gas, and electrical supply are the first thing you need to assess your unit. Plus, shut-off valves are another thing that can cause this issue. They turned off occasionally.

  • Gas Burner

    The gas burner can also cause this issue as it stopped generating sparks. If it happens, it is a sign of classic failure.

  • Error Code

    Error codes appear on your tankless water heater’s control panel if there is a problem with the burner. Check the manual list as it has all the important codes. Note that if there is no error code, you need to fix the issue and reset the heating unit to make it run.

  • Minimum Flow Rate

    If your water heater doesn’t activate the flow rate, it can be a probable cause of “no hot water.” The tankless water heater needs a minimum amount of water to flow and begin heating. You also need to check if the hot water taps are open and there are no obstructions.

When you’re unable to reach the core of the problem, trust the expertise of Gallegos Plumbing and get immediate assistance for professional plumbing services and water heater services in Ventura County, including Thousand Oaks and Newbury Park, to address the problem timely. Give us a call now at (805) 243-2622.

Did you know that not taking proper care of your water heater during the winter may freeze it?

The issue can create problems for indoor units. The pipes leading to the tankless water heater can freeze, or the unit itself may freeze.

Some cold-weather problems are;

Water Freezing Cold or Hot

If a tankless water heater delivers water that is too cold, there can be numerous issues causing this problem.

» Water is Freezing Cold

  • Many people set the water temperature too low. Adjusting it between 120 and 135 degrees can fix the problem.
  • The gas valve is not in good condition and providing low pressure. The pressure reduces if the gas valve is not opened correctly. The narrow gas line can also create this problem.
  • Not flushing your tankless heater twice or thrice in six months may result in limescale buildup inside the exchanger. This buildup serves as a heat insulator and affects the heat exchanger’s ability to transfer heat to the cold water.
  • There might be an issue with venting. Check the system’s venting section and clean it if there is debris. It needs clean space to let fresh air come in for combustion.
  • It can be a plumbing crossover problem in which the hot water mixes with the cold water. If the tankless water heater has a single-lever mixing valve, the issue is not uncommon.

» Cold Water Sandwich

Another common problem that many bigger households often face is the “cold water sandwich.” It usually happens when people take back-to-back showers, which causes hot water to trap in the pipes.

When one person finishes taking a shower, the plumbing line still has some warm water flowing. When the next person turns on the water, it is warm for a few minutes and then turns icy cold as the heater needs to kick in again so it can deliver hot water.

Though tankless units are instantaneous heaters, they need some time to transfer heat to the water. While the heater activates immediately, there are delays as heat takes time to travel through the plumbing.

What are the Solutions?

Remember that the longer the plumbing pipe is, the further the water needs to flow. The cold-water gap depends on this travel time. But you do have some workarounds to troubleshoot this problem.

One cost-effective solution is to know about the holdup and wait until the hot water starts flowing again. But homeowners prefer instant access to hot water throughout the home.

Installing a point-of-use tankless water heater is your second option. They are a practical solution when you need hot water in a remote area. You can use the point-of-use tankless water heater as a booster for your central water heater to fill in the gap.

Rather than risk a DIY tankless water heater installation, have a professional plumbing contractor handle the task.

Other issues related to the tankless water heater include;

  • Venting obstruction
  • Low water pressure
  • Mineral buildup
  • System overload
  • Corrosion
  • Instant shut-offs during shower

Related Article: An Ultimate Guide To Choosing The Hot Water Heater

Summing Up

A tankless water heater is an affordable heating water option for tasks like showering, dish-washing, and launder. The heaters don’t store water and save you a great deal of money. Though these energy-efficient units are excellent for hot water supply, they are not immune to technical problems.

There can be many problems with a water heating unit, from producing “no hot water” to low gas pressure and corrosion. While you must keep performing preventative tasks from time to time, contact Gallegos Plumbing, your professional plumber, for tankless water heater services from repair or maintenance to replacement and installation. Drop us a message today here, or more conveniently, call us at (805) 243-2622 to assess and address the problem.

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