Tankless water heater vibrations

by Timothy Hennip
(Poplar Grove, Illinois, USA)

I have a tankless hot water heater that vibrates, severely. It used to be just a short, somewhat quiet noise that has now grown into a house rattling nuisance.

I have checked and cleaned the filter with no change. I have raised and lower the temperature a few degree’s (1 degree at a time), with no change.

I’m not sure what to do to get vibrations to stop, or at least return to a respectable level. It is so loud now, that my neighbor can heard my house vibrating inside of his house.

Like I said before, this vibration used to run maybe 5 to 10 seconds, and it wasn’t too loud. Now it takes over a minute for the vibrations and the noise to stop. I have my tankless unit mounted with lag screws directly to the studs (nothing in-between, no plaster or sheet rock). I have checked all 4 bolts, and they are all tight. Any advice would be greatly appreciated.

Thanks,

Timothy Hennip