Video Evidence: Serious Design Flaw in old Water Meters
Besides weekly power issues; we also experience constant water problems on a regular basis.
The water taps at our place was making a hissing sound; you could actually hear air blowing from it. For some reason I decided to check the meter outside. As I walked closer to it, I could lterally hear it making a noise. It was running like crazy with NO water in the pipes!
This mechanical water meter accellerates like crazy with air blowing through it
The mechanical water meter type
The municipality has since replaced this old mechanical water meter with a modern ultrasonic meter that does not measure air because ultrasonic transit-time technology requires a continuous liquid medium to propagate sound waves between transducers.
Why It Fails to Measure Air
- Acoustic Signal Loss: Ultrasonic meters send sound pulses back and forth through the water. Air or gas pockets interrupt or absorb this acoustic signal.Â
- The “DRY” Code: When air replaces water inside the measuring pipe section, the meter cannot calculate fluid velocity and stops registering volume flow. It triggers an info code “DRY” on the digital display.
- No Over-Registration from Air Passing: Unlike mechanical meters that can spin falsely when compressed air or bubbles pass through them, an ultrasonic meter correctly registers zero flow or shows the dry alarm until the measuring chamber is fully refilled with liquid.



