FAQ | Sentry


(1) On the QR code scan page, please have the camera scan the QR code on your phone. Make sure that you have heard the camera say “WiFi is connecting” before tapping the “I heard ‘Wi-Fi is connecting’” button

(2) Please make sure that the WiFi hotspot you selected is 2.4Ghz. 5Ghz WiFi is not supported.

(3) Please make sure that the WiFi hotspot uses WPA or WPA2 security

(4) Please double check and make sure that the password is correct

If the issue persist, please contact customer support

If your Sentry doorbell is completely unresponsive, i.e. no lights, no sound, and cannot be reset, regardless of whether it’s powered by USB or doorbell wires, please read ahead. Otherwise, you can try resetting the doorbell.

This issue most likely happens during or after a firmware update. If Sentry somehow lost power or the voltage was not stable during the update, then the update would fail, resulting in a “bricked” state.

To resolve the issue, you would simply need to manually update Sentry’s firmware. We highly recommend using a 5V 2A micro USB adapter to power Sentry during the manual firmware update to provide the most stable power.

The most common cause for frequent disconnection and/or shutting down is insufficient power. Sentry requires a 8-24V AC transformer without a chime, and it’s recommended to use a 16-24V AC transformer when a chime is present. The transformer should have at least 20VA (volt-amps) of power, and the higher the better (e.g. 30VA/40VA).

Common symptoms of insufficient power include:

  • Device frequently restarts
  • Cannot watch live view
  • IR (black-and-white) night vision flickers
  • Device shut down and never powered up again
  • Device shuts down after pressing doorbell button
  • Chime does not ring when pressing doorbell button (assuming that the “Doorbell Chime” option is enabled)

If you encountered one of the above symptoms, please check the voltage and power of your doorbell transformer. If you have a multimeter, you can measure the voltage on Sentry to make sure it’s at least 8V. Please upgrade your transformer if the voltage or power is lower than the requirement.

Just in case, please also make sure that there is a stable WiFi coverage at Sentry’s location.

Please first make sure that the “Doorbell Chime” option is enabled. See this FAQ

If “Doorbell Chime” option has been enabled, it might be caused by insufficient power, please see this FAQ to troubleshoot.

Short answer: you would need to install a resistor (recommended 10Ω(Ohm) 0.5W) across the terminal screws on your mechanical doorbell. See below for example:

Long explanation: It is not uncommon to hear the chime buzz after installing a video doorbell. The reason is that before you installed Sentry, the doorbell button acts as a switch for the electric circuit, so when the button is pressed, the circuit is closed and the chime rings. Sentry requires constant power, so the circuit is always closed, and depending on the power consumption of the chime, there might be enough residual current in the circuit to cause the chime to buzz. Installing a resistor across the terminal screws dissipates the current through the chime, thus reducing the buzzing.

If the camera does not scan the QR code on your phone during the setup process, please try the following:

  1. Make sure that you have heard the camera say “waiting for connection” at least once. If not, please reset the camera
  2. Place your phone about 4 inches in front of the camera, holding it upright and stationary for at least 3 seconds. If you do not hear “WiFi connecting”, move your phone closer or further and hold it again.
  3. Turn your phone screen’s brightness to 100%
  4. Make sure that the WiFi name and password are not too long. It is recommended to keep them under 16 characters. Longer texts make the QR code more complex, and due to the camera’s distortion, it may not recognize a complex QR code.

"How" & "What"

The Sentry doorbell is wired. It requires existing 8-24V AC doorbell wiring.

Alternatively, it also supports 5V 2A DC power source via a micro USB port.

Read more about Sentry’s tech specs here

(1) Upper-quarter Flashing: Device reset/powering up

(2) Lower-quarter Flashing: Connected to WiFi and connecting to server

(3) Left-quarter Flashing: Voice message recording

(4) Right-quarter Flashing: Connecting to WiFi

(5) Full-circle Flashing: Updating firmware

With a few simple tools, you can certainly install Sentry yourself. You can follow the installation instruction in the box, as well as this installation video.

(1) Download the “Bosma” app, create a new account or log in.

(2) Make sure that Sentry is powered and that you have heard it say “system startup” and “waiting for connection”. If you don’t hear these messages, reset the camera.

(3) On the app home screen, tap the “+” button at the top right corner, and select “Sentry”. Then follow the in-app instructions to complete the setup

If you have any issue during the setup process, please contact customer support.

Please make sure that your Sentry is powered. Remove the base plate if it’s on. You should find a reset button with a “RESET” text to its left between the two terminal screws at the top of the camera body. Long-press the reset button until you hear “system reset”. After about 30 seconds, Sentry should power up again and you should hear “system startup” and “waiting for connection”. You can now set up Sentry in the app again.

Please make sure that you heard “system reset” after long-pressing the reset button, and that you heard “system startup” and “waiting for connection” later. If one of these messages was not heard, please contact customer support.

Note: If you intend to use Sentry’s local storage, it is recommended to insert an SD card prior to installing Sentry. Also, please format the SD card to FAT32 before adding it to Sentry.

Slide down to remove Sentry’s base plate, then push back to remove the PIR module on the top. You should now see the SD card slot on the top of the camera body. Push the SD card all the way in with its metal strips facing towards the back of the doorbell, until you hear that it clicks into place. To remove the SD card, push the SD card in again and it should be ejected from the slot. After inserting the SD card, replace the PIR module.

You can also watch the installation video to locate the SD card slot.

(1) Download the latest firmware here.

(2) Unzip the files and copy the files to the root folder of a micro SD card (Please make sure that the SD card is formatted to FAT32)

(3) Disconnect Sentry from power and insert the micro SD card into Sentry (where is the SD card slot?). If Sentry was installed, you will need to unmount it from the base plate.

(4) Power up Sentry again (it is recommended to use a 5V2A micro USB adapter to power it up). Immediately (within 1-2 seconds) after Sentry is connected to power,  long-press the RESET button at the back of the doorbell body for about 3 seconds. You should now see the doorbell indicator light flashing fast in full circle.

(4) Wait for about 2 minutes. When you hear “system startup” and “waiting for connection” at the end, the firmware update is successful.

(5) Please remember to unmount the SD card and delete the firmware update files before using it on Sentry again.

Yes. If your doorbell wiring is connected to an existing chime, you can enable doorbell chime support in Sentry Home -> Settings -> Doorbell Chime.

Warning: Before enabling the Doorbell Chime option, please make sure that a doorbell chime is properly installed. Enabling this option without an existing chime may damage the Sentry doorbell and/or your transformer and could pose a serious fire risk when Sentry’s doorbell button is pressed.

Yes. You can power Sentry with a 8-24V Low Voltage Transformer directly.

Warning: If you do not have a doorbell chime also connected to the transformer, please do NOT enable the Doorbell Chime option

There are two types of voice messages for Sentry.

(1) No Answer messages: Voice message played when you did not respond to a doorbell ring on the Bosma app in time (about 20s)

(2) Busy messages: Voice message played when you selected to “ignore” a doorbell ring on the Bosma app


You can manage voice message settings in Sentry home -> Voice Responses. To add a new voice response, tap the “+” button at the top right corner. To enable a voice message, enable the “Go to Voice Messages when busy/no one answers” option (if this option is disabled, visitors will not hear a voice message and cannot leave a voice message to you either).


There’s also an “Enable Voice Message” option on Sentry’s home page. If this option is enabled, when someone is ringing the doorbell, you will not receive a notification and Sentry will play the “Busy” voice message automatically. You can use this option when you do not wish to be disturbed.

If you purchased the Aegis door lock single unit, its package comes with a WiFi bridge/connector to connect it to the internet. However, if your purchased a Sentry + Aegis bundle, Aegis can use Sentry as a bridge/connector for internet connection. Please go to Aegis settings -> Manage Fingerprints to pair your Aegis with your Sentry.

Your Aegis door lock can use the Sentry doorbell as a Gateway to connect to the internet (if you purchased just the Aegis door lock, there should be a separate Gateway device in the box that serves the same purpose).

First please make sure that your Sentry doorbell has the fingerprint reader module. The module is available if you purchased the Aegis + Sentry bundle.

Install and set up both your Aegis and Sentry. Then, go to Sentry home page -> Fingerprints, and add your Aegis under “Paired Devices”. Don’t forget to enable “Unlock” under “Fingerprint Actions” so that fingerprint scans unlock the door. You can then add new fingerprints under “Normal Fingerprints”

Bosma Assist Features

For general Bosma Assist FAQs, refer to Bosma App FAQ

Please first make sure that you have an active Bosma Assist subscription, and that you have added this Sentry device to the subscription

(1) You can find them in Sentry home page -> Cloud Videos

(2) You can also find them in Home page -> Bosma Assist ->  Cloud Videos

Yes. If your Sentry has a micro SD card, it’ll also save video recordings to the SD card, regardless of whether a cloud storage subscription is active.

Please first make sure that you have an active Bosma Assist subscription, and that you have added this Sentry device to the subscription.

After you successfully added familiar faces, please make sure Facial Recognition is enabled in Sentry Home -> Settings -> Event & Notification -> enable “Person”

Sentry Home -> Settings -> Event & Notification -> enable “Package”

  1. To use Package Detection and Active Theft Prevention, you must have an active Bosma Assist Pro subscription, and your Sentry doorbell must be added to the subscription
  2. The Sentry camera must have a clear view of the package. If the package is partially or fully blocked from the camera’s view, Sentry may not be able to detect it.

Theft prevention will not be triggered if the Sentry doorbell recognizes a familiar face. Please create a new face profile for yourself (and your family members if necessary) at Sentry Home -> Facial Recognition.