How to Descale a Tankless Water Heater

How Often to Descale a Tankless Water Heater

Tankless water heaters are amazing from many points of view, with energy efficiency, lower utility costs, and less maintenance standing out as selling points.

Do tankless water heaters need a lot of maintenance? Why?

As long as you’re taking good care of it, your tankless water heater can last for more than two decades. Its durability depends on many factors, from proper installation, maintenance to the hardness of water, and many more.

Even if they don’t include a tank and water doesn’t have time to stay in the system, the risk for corrosion is never null. Tankless water heaters are advertised as “low-maintenance”, which isn’t entirely false. However, you should take it with a grain of salt, simply because hard water affects all types of water heater systems, tankless included.

Why does hard water matters so much for a tankless water heater?

You can very well check the hardness of the water in your region online, especially since, in some areas, it may be more damaging for your water heater.

Hard water is when the water in your area carries lots of minerals, calcium, and magnesium mostly. When we talk about tankless water heaters, the minerals can collect inside the heat exchanger, andcan even clog up the passages where water was supposed to run. Soon enough, the water heater is going to struggle for heating the water, which can only alter its durability.

Therefore, the tankless water heater isn’t going to last as long as it was supposed to, increasing the energy bill. It’s because the unit would have to work for longer and use more energy for heating the water. Besides, the mineral buildup on the heat exchanger may damage the water heater for good. You may have to change the heat exchanger or the whole water heaters. The damage caused by minerals to the heat exchanger isn’t cover by the manufacturer’s warranty.

During a maintenance visit, the professional plumber will descale (de-lime) the tankless water heater, eliminating buildup around the heating elements.

The professional plumber should descale the water heater once a year. However, in some situations, you may have to descale the unit more often than once a year.

What are the exceptions from the once a year maintenance rule?

It’s better to descale the tankless water heater once a year. Here’s when you should do it even sooner than once a year:

  • You live in a region with hard water

Frankly, no matter where you live on this planet, the water coming into the system will still carry some amount of minerals. However, the water in some areas is harder than in others. It means that it carries more minerals in it.

Should you live in a region with really hard water, you have to descale the tankless water heater twice a year. It’s one of the best ways to make sure that your heat exchanger doesn’t get damaged by the water.

Check the hard water maps online to find out if the water in your area presents low or high concentrations of hard water. There are many ways with which you can protect the systems in your home from hard water, so do your bits and bobs about it.

  • You set the unit to a high temperature

When the temperature of your water heater is set too high, the risk for scale buildup is higher, especially if you add very hard water into the picture.

It’s because many chemicals will dissolve faster when you apply heat. Very hot water will cause the limescale to buildup really fast around the heating elements of your tankless water heaters.

Now it’s a good time to check the thermostat of your tankless water heater. What’s the set temperature? Is the thermostat displaying a temperature higher than 120F degrees? If so, you should get in touch with a professional plumber to clean and descale the mineral buildup from the unit’s heat exchanger.

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