Cleaning A Tankless Water Heater

How to Clean A Tankless Water Heater in 10 Steps

One of the many benefits of tankless water heaters is their low risk of corrosion and durability. Since they don’t have a tank for collecting water, the water doesn’t get to stay much in the system, so tankless water heaters will not destroy any time soon.

Flushing and using a water softener are going to help for the durability of tankless water heater systems, but they will not eliminate the risk for mineral buildup completely. Over time, the minerals may build up and even erode the walls inside the heating chamber.

You need to flush and remove the mineral deposits for cleaning and maintaining the tankless water heater in tip-top shape. Run the procedure once a year (at least), according to the hardness of the water in your area.

What steps to take for cleaning a tankless water heater?

When it comes to maintaining and cleaning devices, it’s always better that you are meticulous and don’t skip any steps. Here’s how to clean your tankless water heater properly:

   1. Start with shutting down the power source for your tankless water heater.

Should you have a gas model, you need to shut off the main gas, whereas, for electrical models, you have to turn off the circuit breaker.

   2. Close and turn off the water valves linked to the water heater

It’s important not to skip this step as you don’t allow cold water go back into the water heater. You also need to keep the hot water from coming out as you’re cleaning the unit.

The water valve for the cold water may be blue, whereas the one for hot water should be red. You may also have a third valve running the water inside your home.

   3. Put the purge port valve caps away

Typically, purge valves feature tiny handles similar to the letter “T.” By removing the caps, you will eliminate any pressure built inside the pipes and reduce the risk for excess hot water from coming out and touching your skin.

As you’re removing the purge port valve caps, a pressure may appear. You must be 100% sure that the hot water is shut off for safety reasons.

Handle the caps extremely gentle so that you don’t move the rubber washer sealing discs since they’re fundamental for a proper function of the valves.

   4. Connect the hosing lines to the valves

Not all manufacturers include hosing lines with the tankless water heater, but you can buy them from a retails store for water heaters and home repairs. The hosing lines need to be quite long, going from the unit to the bucket.

When it comes to this step, it’s better that you check the user manual from the manufacturer. You can also contact the manufacturer if you have any issues regarding this step.

A sump pump may be necessary for some situations. It will link the hoses discharging and flushing the water from the unit with both cold and hot water valves.

   5. Twist the port valves perpendicularly to the position of the hot and cold water

You can use 2.5 gallons of undiluted white vinegar for cleaning the tankless water heater. Many use chemical solutions, but white vinegar is a great choice nine times out of ten.

It’s also common for people to use the tankless water heater as a source for drinking and bathing water, so it’s better that you don’t use chemical cleaning solutions. They can pose an important risk for your health.

   6. Go to the user manual once again

It’s time to flush and drain your unit, but every tankless water heaters come with specific instructions provided by the manufacturer. Expect to spend 45 minutes or so for this step.

   7. Close the purge port valves

You can close them by twisting the “T” shaped handles once the flushing process is done. Don’t forget to disconnect and put the hosing lines away from every water valve.

   8. Put the purge port valve caps back on

It’s also time to replace the caps onto the purge valves, tightening the caps entirely. However, make sure that you don’t break the rubber sealing discs placed inside the caps.

   9. Check the manufacturer’s manual once more

You have to look in the manufacturer’s manual and find the precise instructions on what’s the best way to re-start the water heater.

Most of the time, you’re only going to have to rotate and open the cold and hot water valves. They should be parallel to the position of the main valve that goes into the house.

   10. Complete the cleaning process

You end up the cleaning with turning on the hot water tap in the sink quite slowly. You want to let the air go through the pipe. Have patience and wait until the water is running again steady, with no air escaping. It’s only going to take a couple of minutes.

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