How to Descale a Tankless Water Heater?

How to Descale a Tankless Water Heater?

All housekeepers have to take great care of their houses. It is necessary to give heed to every detail, and a tankless water heater is one of them. In fact, it’s not a small detail but a very important part of the entire house. Although a traditional tank-style water heater gathers more calcium, a tankless heater also needs some cleansing. Not all people know how to descale it and want to find some contractors. Nevertheless, everything can be done on your own!

All you require is to read our informative guide. It contains the necessary smart tips to make your water heater clean. After you follow them, we guarantee that you will return a tankless water heater recirculation. Therefore, be attentive and try to memorize all the steps and facts. They are very simple.


Before you begin to descale the device, you should get ready for that. You ought to acquire certain things. These are:

  • A 5-gallon bucket;
  • Two drain hoses (in most cases, they need to have a ¾-inch connection);
  • A submersible pump;
  • 4-gallons white vinegar.

The necessary stuff can be bought in any specialized store. Perhaps online stores are more beneficial due to cheaper prices. As you can see, there is nothing extraordinary. The main thing you require is white vinegar. It means that the maintenance of your water heater will not cost much. Moreover, it is recommended to descale it only once per year. Mind that it will take about 60-90 minutes to complete this vital and simple task.

Notion! You should give heed to the quality of water. If it is hard, you will have to do this procedure more frequently. You will probably notice when the time comes. However, we want to give one smart tip. There are various water heaters and some of them have smart indicators. This indicator will tell you when maintenance is required. Consider choosing this option for your convenience and on-time warnings.

Steps to Follow

Now, after you have acquired everything, you may begin to descale your tankless water heater. Be attentive and do not miss a thing. Steps are, however, simple.

  1. Turn Off the Unit

The first thing you should do is to turn it off. It is required for your safety. If your unit is electric, find the electrical circuit. It’s supposed to be at the breaker panel. Obligatorily check whether it is truly off.

You should get into a terminal. Make sure you use a non-contact tester to be safe from electricity. If the lights are on, it means the unit is still at work. Begin the maintenance only when the lights are gone.

In case you use a gas unit, simply turn the gas valves in the necessary position.

2. Turn Off the Water Supply Valves

The second thing to do is to put off the supply valves that let the water dash through the system. Mind that you should turn off valves that are responsible for cold and hot water. Commonly, they are located below the heating unit. Your unit may have a special draining valve, which will get rid of the water that possibly remains inside.

3. Connect the Hoses

The third step is the connection of the hoses. This process is also very simple. Take one end and connect it to the cold water valve. Another end ought to be connected to the submersible pump. After you connect the hose to the hot valve, make sure the other end lies in the bucket. Make sure all the connections are fixed firmly to avoid splashing water all around.

4. Use Vinegar

Now, the time has come for our vinegar. Pour all 4 gallons right into the bucket. Make sure the end of the hose, which is connected to hot water, is also in the bucket!

5. Turn On the Pump

The next step is to activate the pump. Turn on the hot water pump. Such pumps simply needed to be plugged into the wall to function. Make sure you place the connection of the hose in the bucket first and only then turn on the pump. Leave it functioning for about 45 minutes and afterward turn it off. Wait until you are confident that all the water is drained.

6. Clean the Air Intake Filter

Make sure the air intake filter is clean! You should clean it according to the instructions in the manual of your heater. As there are various models, we cannot say for sure how it should be done. Everything depends on a certain model, but it is never hard to fulfill this action.

7. Rinse Your Water Heater

The last crucial step is to clean the water heater. After everything is drained, remove the hose that was connected to the cold water valve (the hot one remains in the place!). Let the water pour down into the bucket to get rid of the wastes. When you see that the bucket is almost full, turn the valve off, getting rid of the water. Stop when you are sure all the water is drained from the system.

8. You May Turn It On Again!

This is it! You have come to the last phase of the descaling process. Detach everything you have connected and check the system. Check hot water. If it runs, you have done everything correctly and your descaling process was completed successfully. Congratulations!

The Bottom Line

We hope you find our informative guide useful for you. Of course, you are free to look for similar guides, but we assure you that it will be a plain waste of time. They will not differ from the instructions we have provided above. This process is very simple, and you can easily repeat it without our guide if you fulfill it a couple of times.

Look for other guides written by us. We are always happy to help all housekeepers to secure their houses, machinery, and all devices they need to clean or repair.

Read More: How to choose Sunglasses: Practical Advice