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Poor Ultrasonic Signal: What It Means and How to Fix It

Updated over 2 weeks ago

Quick Answer

A poor ultrasonic signal usually means Bluebot isn’t making clean contact with the pipe, the pipe isn’t ideal, or the app settings don’t match the actual installation. Most issues are resolved by improving pipe contact, alignment, or correcting the pipe type in the app.


What Is Ultrasonic Signal?

Ultrasonic signal measures how well Bluebot’s sensors can send and receive sound waves through the pipe and water inside it. A strong signal is required for accurate flow readings.

In simple terms:
Clean pipe + tight fit + correct alignment = good signal.


When Should I Worry About Signal Quality?

You may need to take action if:

  • The app shows Poor or Weak Signal in settings

  • You are not getting accurate readings


Most Common Causes (and Fixes)

1. The Device Isn’t Snug Against the Pipe

Why it matters:
Even a small air gap weakens the ultrasonic signal.

What to do:

  • Install on at least 4 inches of straight pipe

  • Make sure the device is tightly clamped

  • After clamping, give the device a firm squeeze to close any gaps


2. The Pipe or Pads Are Dirty

Why it matters:
Paint, dirt, grime, or debris block ultrasonic transmission.

What to do:

  • Sand the pipe using the included sandpaper

  • Wipe clean with the microfiber cloth (slightly damp works best)

  • Remove the device and inspect the pads

  • Clean pads with warm water and mild soap, or replace them if dirty


3. Pads Picked Up Dirt From Multiple Install Attempts

Why it matters:
Ultrasonic pads are sticky by design and easily collect debris.

What to do:

  • Use the included silver C-holders to prop the clamps open

  • Remove the old pads

  • Install a fresh set of replacement pads directly over the clear sensor windows


4. Installed on the Wrong Pipe

Common mistakes:

  • Hot water line instead of cold

  • Gas line instead of water line

  • Partially full or empty pipe

What to do:

  • Confirm the pipe is cold and pressurized

  • Never install on gas lines

  • If unsure, locate the main shutoff valve — this usually confirms the main water line


5. Pipe Has Internal Scale or Corrosion

Most common in:

  • Older homes (pre-1970)

  • Areas with hard water

  • Galvanized or older copper pipes

Why it matters:
Internal buildup thickens the pipe wall and weakens the signal.

What to do:

  • Try a different section of pipe

  • Consider a plumber inspection if corrosion is suspected


6. Pipe Size Is Not Supported

Bluebot supports specific pipe sizes and materials.

What to do:

  • Confirm your pipe size and type are supported

  • Review the Compatibility & Specifications article if unsure


Alignment Issues

Device Is Angled or Off-Center

Why it matters:
Sensors must sit directly over the pipe centerline.

What to do:

  • Remove the device

  • Reinstall it straight over the pipe

  • Use the “^” alignment notches on both sides as guides


Installed Over a Fitting or Elbow

Why it matters:
Fittings and bends cause turbulent flow, which affects accuracy.

What to do:

  • Move the device to a longer straight section

  • If outside space is limited, consider installing indoors near the water heater or filtration system (on the cold line)


Fix During Setup

  • Restart the setup process

  • Remove the device from your dashboard

  • Complete the site survey again

  • Select the correct pipe type before scanning


Still Seeing Poor Signal?

If you’ve:

  • Cleaned the pipe and pads

  • Confirmed alignment and pipe type

  • Verified the pipe is correct and pressurized

…and signal is still poor, contact Bluebot Support or send a photo of your install location. We’re happy to help.

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