Skip to Content

NuTone doorbell troubleshooting & How-to guide

NuTone doorbell troubleshooting & How-to guide

When it comes to doorbells, NuTone takes the cake based on their features, performance, and price point. They make guest interaction a breeze. Not to mention the security benefit of being able to see who is at your door from a remote location. However, they are prone to issues just like any other smart gadget.

Here are some easy tips to help you troubleshoot and fix your NuTone doorbell. As well as some how-to advice to help you use your NuTone doorbell with ease.

How do you hook up a NuTone doorbell?

The most important part of setting up your NuTone doorbell is the wiring. Wired doorbells allow you to receive door signals from multiple entrances. It also allows you to set up a chime to let you know when someone is at the door.

You can wire your NuTone doorbell to rechargeable batteries or directly into the electric connection. You can do the wiring yourself or hire a certified electrician to do the job. Go for the battery-powered option if you cannot connect the doorbell to your electricity grid.

Check this too: Nest Doorbell How to & Troubleshooting Guide

That said, here are the steps to follow when setting up your doorbell;

Hard-wiring the doorbell

  • Turn off the power at the circuit breaker before starting the wiring process.
  • Then mount the transformer into the junction box. And connect the power to the transformer.
  • Then run the two conductors 18-22-gauge wire from the transformer terminals and the wire from the pushbuttons terminals to the doorbell unit. And finally, connect the wire between the pushbuttons.
  • Then attach the wires. Ensure you attach the wires to the transformer terminal. And connect the transformer to the rear door push button.
  • Then connect the rear door push button to the front door push button.
  • Finally, connect the pushbuttons to the correct terminals. And test the doorbell.

Battery setup

  • Run the two conductor 18-22-gauge wire from the pushbuttons terminals to the doorbell unit.
  • Then connect the wire between the pushbuttons. Ensure you connect the battery connection to the rear push buttons. And connect the rear push button to the front door push button.
  • Connect the correct terminals to the push buttons and ignore the transformer terminal.
  • Once you are done with the wiring, test the doorbell to see if it is working.

Note: hire a professional if you are not able to handle the connection yourself. You should also refer to your user manual diagrams for further clarification.

Why is my NuTone doorbell not working?

In most cases, the culprit is low voltage. To rectify this, all you have to do is fasten the wire connecting the buttons to the power source. If this does not work, the button may be broken and needs to be replaced. If your button does not buzz when pressed, it needs to be replaced.

You should also check to see if the button is clogged with dirt, which may also prevent it from working. Press the button severally to see if it sticks. Then clean with rubbing alcohol and a Q-tip and spray it with WD-40 to dislodge trapped debris.

Alternatively, the cause of the malfunction may be a result of faulty wiring, a broken chime box, or a damaged transformer. Troubleshooting these issues requires using a voltmeter to see if there is continuity. Remove the doorbell cover and dismount the doorbell so you can check if electricity is flowing through the various parts.

Chime box damage

Remember to disconnect the power before starting the troubleshooting process. Then proceed to check if the chime box is damaged. Start by removing the mounting bracket, then remove the cover to access the chime box’s wires to the button.

Use a voltmeter to test for current continuity. If it has a signal but not sound, it means the chime box is damaged and needs replacing. If the issue is electric current continuity, then hire a professional to fix the connection.

Damaged Transformer

Then, cut off the power and then check for loose wires before performing the current continuity test using a multimeter or a voltmeter. If the voltage reading is too high, then the transformer is damaged. On the other hand, if the voltage reading matches the voltmeter reading, then it is okay.

A low reading is a test fluke, and you should adjust the voltage range and repeat the test. If the voltmeter readings do not match, replace the transformer. Or hire a professional to handle the job.

Faulty wiring

Inspect the wiring to see if it has become loose or water damaged or rodent has chewed it. It may also be frayed or bent. If the faultiness is caused by one of the issues, fix it as needed. Also, check to see if the insulation on the wires is damaged and fix using electrical tape.

Then text current continuity using a voltmeter. If there is no signal, then you need to replace the wiring. You may need to hire a licensed professional to handle the wiring job. 

How do you remove the NuTone doorbell cover?

Start by shutting off the power to ensure you do not get electrocuted. Then lift the cover from the bottom. The cover will lift, and you can easily detach it from the doorbell and remove it. For an older NuTone doorbell model, you may need to use a screwdriver to remove the screws so you can remove the cover.

How do you replace a NuTone doorbell transformer?               

Once you have determined that the transformer is damaged, follow these steps to replace it;

Items needed:

  • Non-contact voltage tester
  • Screwdrivers
  • Pliers
  • Replacement doorbell transformer (must have same voltage rating as original)
  • Wire strippers (as needed)
  • Wire connectors (as required)


  1. Disconnect power to prevent electrocution.
  2. Use the volt tester to test for current continuity to ensure the power is truly off. It is better to be safe than sorry.
  3. Then disconnect the wires connecting the transformer to the junction box.
  4. Then remove the old transformer by loosening the mounting nut using the pliers. This will detach the transformer from the box.
  5. Mount the new transformer into the junction box and connect the wires securely.
  6. Ensure you connect the wires correctly.
  7. Use the voltmeter to check for continuity.
  8. Reassemble the rest of the wires in the junction box.
  9. Then turn the power back on and test to see if the doorbell is working.
  10. If you are unsure about the process, hire an electrician.

How do you disconnect a NuTone doorbell power?

You can turn off the doorbell power by turning off the circuit breaker responsible for supplying electricity to the doorbell. Or you can remove the doorbell transformer as it connects the doorbell to the electrical circuit.

Can you get shocked by doorbell wires?

No. the doorbell operates at such a low voltage it is unlikely to shock you. However, when troubleshooting the transformer or handling its wiring, you may get shocked as the wiring are line-voltage circuit wires. As such, you should always turn off the power when working on the doorbell.  Or hire a licensed electrician to handle the electrical bit.

What voltage is a NuTone Doorbell?

NuTone doorbells operate on 8-24 volts. This ranges from model to model. Older models use lower voltage. They are compatible with standard 120-volt household voltage but require a transformer to reduce the voltage to the required voltage. 

How to adjust the volume on a NuTone doorbell

This varies from model to model. Older models do not have the volume adjustment feature. To increase the volume on a doorbell without inbuilt adjustment features, use a chime extender. To reduce or increase the volume on an intercom station, use the volume control to adjust the volume.

For newer models, adjust the volume on the doorbell as mentioned in the user manual. Another way to increase your NuTone doorbell volume is by changing the transformer to one with a higher voltage. This will automatically cause a change in chime volume.

How to reset a NuTone doorbell

To reset a NuTone Intercom Master station (IM3303/IMA3303), press the Memory set button on the intercom’s bottom right corner after opening the panel cover. Push the button until it clicks, and then press for at least 5 seconds to reset the memory.

You will need to reprogram the clock after the reset. For more details, refer to the user manual.

How to fix a jammed doorbell

If the doorbell button is stuck, then you need to unscrew the doorbell cover and use a Q-tip dipped in rubbing alcohol to clean the doorbell and reassemble. Also, check to see if faulty wiring is causing the button to jam and fix as needed.

You can also use an electrical contact cleaner or fine sandpaper to clean the doorbell button. If the button is broken, then replace it as a broken side may be causing it to jam.

NuTone Knock video doorbell LED indicator codes and their meaning

Color: Solid blue

Meaning: Transformer voltage is too high

Solution: Locate and replace the transformer with a 10-20 VAC transformer

Color: Slow flashing blue

Meaning: Cold start at low temperature

Solution: Wait for the doorbell to begin powering up (LED will turn solid red)

Color: Fast flashing blue

Meaning: Transformer voltage is too low

Solution: Wire the doorbell without the chime box by following step #7 in the installation instructions

Color: Solid red

Meaning: The doorbell is powering up

Solution: Wait a few minutes until the LED color, and it will change to solid blue

Color: Slow flashing red

Meaning: The doorbell is not connected to the Wi-Fi network

Solution: Follow the user manual steps to connect the doorbell to Wi-Fi in the NuTone Knock app

Color: Fast flashing red

Meaning: The doorbell is updating its firmware

Solution: Wait for the updates to complete it will only take a few minutes

Color: Flashing green

Meaning: Doorbell is connecting to the cloud server

Solution: Wait till it changed to solid green

Color: Solid green

Meaning: The doorbell is connected to the cloud server and ready to use.

How to connect the NuTone Knock to Wi-Fi

  • Press and hold the doorbell’s call button for at least 10 seconds until the LED starts flashing red and green.
  • Log into the NuTone Knock app and click on the gray “+” at the screen’s bottom right.
  • Then select the “Add your new doorbell camera” option.
  • Go to your mobile device’s settings menu and select the doorbell (“DCAM100###”) in the Wi-Fi settings subcategory.
  • Then click “Next” and set a password for the doorbell.
  • In the mobile device’s Wi-Fi settings, select your home’s Wi-Fi network.
  • And do the same in the NuTone Knock App. Ensure your mobile device and the doorbell are connected to the same network to complete the Wi-Fi setup.
  • Then enter your Wi-Fi network’s password in the app. This grants the app access to your Wi-Fi network.
  • Once the connection is established, the LED ring will emit a solid green light.
  • The firmware with update automatically if a software upgrade is needed.

Why can’t people hear me on my NuTone knock video doorbell?

The main reason people may not hear you is that the mic is not on your end. Check to see if the mic is on and turn it on if it is not on. Another reason is low speaker volume. To increase the doorbell speaker volume, go to the NuTone Knock app and click on the menu.

Then, go to the system settings, select doorbell volume, and adjust the volume by moving the slider to the right until you reach the desired speaker volume.

Why can’t I hear visitors during a live call?

Check to see if you have selected the correct sound output option on the app. The options are earpiece or via your phone’s speaker. You can choose the listening option by clicking on the earpiece or speaker on the NuTone Knock app live view screen.

How to update NuTone doorbell firmware

  • Log into the NuTone Knock app and tap the three lines in the screen’s upper right corner to open the menu.
  • Click on About Devices and select Doorbell Cameras.
  • Then click on the name of your doorbell camera and tap “Update Firmware.”
  • Then wait for the firmware to update. It will only take a few minutes.

My NuTone doorbell power cycles on and off.

Ensure the doorbell does not have faulty wiring by manually inspecting the doorbell wires following the steps discussed above. Then check if the doorbell is receiving electric current by testing for current continuity using a voltmeter.

Check this too: Ring Doorbell Pro Troubleshooting: Issues and Fixes

If the wires are loose or damaged, tighten them or replace them respectively. If the wires are not connected correctly, redo the wiring or hire an electrician to do it. Finally, check to see if your electric connection is the issue and hire an electrician to fix it.