Tankless Water Heater Repairs


Tankless water heaters are an excellent option for today’s homes. They can keep up with the demand for hot water in most households, if they are sized correctly, they cut down on energy cost, and will not run out of hot water the way standard storage tank water heaters do. All of us at H20 plumbing and water heaters are professionally trained to install and service tankless water heaters, so if you live in the middle Tennessee area and are interested in a tankless water heater or need service repairs on one then please give us a call at 615-864-9459. Our plumbing specialist will gladly come out and help you with any problems or ask any questions you have.

The good advantage of a tankless water heater is that they require fewer repairs over their lifetime on average than storage tank water heaters. That does not mean that they will not break, however! Any type of water heater will have problems. Let us take a look at some potential water heater problems below.

Problems With Hard Water

The water that enters a tankless water heater moves through small tubes in the heat exchanger, and this will cause problems if there is a build up of calcium and mineral deposits. It will start with a drop in the water pressure, and then followed by no hot water at all. The prime reason is that hard water minerals build up in the system. You will need to have the water heater cleaned and flushed out, and we also strongly recommend installing a water softener to eliminate the problem at the source. You can read about water filtration in another article here.

Venting Issues

Gas fueled water heaters must vent out combustion fumes safely from the system. If a water heater has poor ventilation from improper flue pipe or crushed flue pipe, acidic condensation will start to develop inside the heat exchanger and quickly ruin it. Poor venting is also a potential safety risk due to carbon monoxide. This problem is unlikely to happen,as long as the water heater was professionally installed to have the correct sized venting. Tankless water heaters can also be installed on the out side wall of the home or building and this eliminates this issue, as long as it is away from a window.


Corrosion is the enemy of all things that are made out of metal and water can be in contact with it. A tankless water heater is less likely to corrode inside it than a storage tank system, but if the pipes start to leak, corrosion can start up. If the corrosion gets too far, the whole system will probably need to be replaced. This is why it is important to act on any leaks you might notice with the water heater.

Trouble With The Burners

The most popular style of tankless water heaters is a natural gas fueled model. There are electric models, but they cost much more to run. A gas fueled tankless system has to use burners just like a tank system or a furnace. The difference is the burners apply heat to water moving through the heat exchanger, rather than to a standing water supply, and the burners only come on when there is a demand for water. These burners can become dirty and get clogged, which will cause them to have trouble firing, and you will notice this by a drop in hot water temperature in the house. The flame sensor can also get dirty. The burning of the gas will leave a sulfur residue on it over time and it will start to not sense the flame correctly. this is easily remedied by cleaning it. Sometimes it may need to be replaced also.

A Failed Heating Element

This only applies to electric tankless water heaters. If the heating element burns out then there is no heat to apply to the water. Call a professional to ensure this work is done correctly.