Tankless Water Heater Noisy Pipes

Water vapor is a byproduct of combustion although in this case the vapor contains elements such as methane nitrogen and oxygen.

Tankless water heater noisy pipes.

Other sources of noise include blocked or inadequate ventilation or a defective or improperly set pressure valve. The sensor controls the amount of gas sent to the unit. In that case you need to have a plumber install a check valve in the water line. Even though a toilet only uses cold water i have seen some toilets do this.

Inside a condensing tankless water heater the combustion process superheats the water that enters your shower sink etc. A blocked or improper ventilation and even a defective or wrongfully set pressure valve can also make your tankless water heater loud. Or you can try to run down the leak yourself by checking the following. If you hear a weird groaning sound from the pipes or the tankless hot water heater when you flush the toilet that could be the culprit.

Generally speaking there is a lower chance of hearing strange noises with a tankless water heater vs tank model. Another standard issue that causes loud noises in tankless water heaters is a dirty flow sensor. If the running water noise continues once the tank is filled you may want to call a professional plumber to investigate the situation for you. Good luck with your project.

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.