An experienced plumber explained that the tapping noise could be gas trapped under sediment at the bottom of the tank. As the gas rises the bubble “explodes”, creating a tapping noise. Draining the tank could remove some of the sediment, but the best thing is to call a professional for help.Mar 6, 2016

Why is my tankless water heater knocking?

Another common problem that can create noise in tankless water heaters is a dirty flow sensor which controls how much gas is sent to the unit. Other sources of noise include blocked or inadequate ventilation or a defective or improperly set pressure valve.
Feb 17, 2016

Why does my water heater make a tapping sound?





The knocking noise from your water heater is caused by scale, which is a buildup of sediment, at the bottom of your heater.
Mar 2, 2020

How do you fix knocking water?

Here’s how:

  1. Shut off the water to your home at the main.
  2. Open the highest faucet in your home.
  3. Open the lowest faucet (it’s usually outside or in the basement) and let all the water drain out. …
  4. Turn the lowest faucet off (the one you opened in step #3) and turn the water main back on.

Do tankless water heaters make noise?

Tankless water heaters will all make some noise when starting up and heating water, but the noise levels are usually reasonable and not cause for concern.
Nov 16, 2015

Can a tankless water heater explode?

Because there is no tank which can overheat or experience a massive spike in pressure, a tankless system doesn’t have the danger of bursting or exploding. A tankless system is also a safer device to have with children around.
Dec 28, 2015

How much noise do tankless water heaters make?





Gas tankless hot water heaters all make noise when firing up and heating water, but the levels are usually less than 90 decibels. A decibel meter can be used to find out how loud your tankless water heater actually is.

What maintenance is needed on a tankless water heater?

The good news is that tankless water heaters don’t require much maintenance, either. A tankless system should be serviced as a part of the regular preventive maintenance that heating and cooling systems receive. Electric or gas components should be inspected.

What is the average lifespan of a tankless water heater?

15 to 20 years

One of the most common questions asked by consumers about tankless water heaters is how long they will last. A tankless water heater can last anywhere from 15 to 20 years with proper maintenance and operation. In comparison, a standard tank water heater normally has a working life of 10 years or less.

What is the downside of a tankless water heater?



The main disadvantage of tankless water heaters is their upfront cost (unit and installation) is significantly higher than tank-style heaters. Including installation, tankless water heaters cost 3 times more than tank-style water heaters on average.
Jan 11, 2022

How do I flush a tankless water heater?

Quote from the video:
Quote from Youtube video: Tell me that you can use vinegar. Instead of a chemical to do this. But if you use vinegar you need to let it flush for about an hour and a half to two hours and also when you use vinegar.

How often do you need to descale a tankless water heater?

During a regular maintenance visit, a professional will descale, also called delime, your tankless water heater to make sure there’s no buildup around the heating elements. A professional should descale your water heater at least once a year.
Nov 2, 2017

How often should tankless water heaters be serviced?



once per year

Just like a tank unit, tankless water heaters need to be flushed once per year. Homeowners with hard water should consider flushing and cleaning the unit even more frequently, perhaps every six to nine months because of the excess amounts of magnesium and calcium found in hard water supplies.

How much vinegar does it take to flush a tankless water heater?

4 gallons

Use 4 gallons (15.1 liters) of undiluted white vinegar to clean your tankless water heater. Never use chemical solutions of any kind.

How long should I run vinegar through my tankless water heater?



Allow the vinegar to circulate through the heater for a minimum of one hour (longer if the pump runs at less than four gallons per minute). This breaks down the scale and flushes out the sediment.
Jan 28, 2020

Can you run CLR through a tankless water heater?

You can use small amounts of CLR with distilled vinegar to clean a tankless water heater. It safely removes calcium, lime, and rust deposits from several household wares, including coffee pots, showerheads, toilet bowls, and washing machine basins.
Apr 28, 2022