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Shelly Plus Smoke User and Safety Guide

Shelly Plus Smoke in action

Read before use

This document contains important technical and safety information about the device, its safety use and installation.

⚠ ATTENTION! Before beginning the installation, please read carefully and entirely this guide and any other documents accompanying the device. Failure to follow the installation procedures could lead to malfunction, danger to your health and life, violation of the law or refusal of legal and/or commercial guarantee (if any). Allterco Robotics EOOD is not responsible for any loss or damage in case of incorrect installation or improper operation of this device due to failure of following the user and safety instructions in this guide.

Shelly® devices are delivered with factory-installed firmware. If firmware updates are necessary to keep the devices in conformity, including security updates, Allterco Robotics EOOD will provide the updates free of charge through the device embedded Web Interface or Shelly Mobile Application, where the information about the current firmware version is available. The choice to install or not the Device firmware updates is the User’s sole responsibility. Allterco Robotics EOOD shall not be liable for any lack of conformity of the Device caused by failure of the User to install the provided updates in a timely manner.

Short description

Shelly Plus Smoke (the Device) is a smart photoelectric smoke alarm, which is effective at detecting slow fires that smolder for hours before bursting into flames.

Sources of these fires may include burning cigarettes left on couches or bedding.

Learn more about Shelly Plus Smoke and its specifications.

Shelly Plus Smoke overview

A: Buzzer
B: Control button
C: LED indication
D: Smoke inlet


  • Battery operated: Replaceable lithium battery helps to extend the lifetime of the Device.

  • LED indication: Light flashes approximately every 53 seconds confirming the smoke alarm is powered and working normally.

  • Low battery warning: Alarm beeps every 53 seconds when the battery is low.

  • Alarm pause (Hush mode): Silence your smoke alarm device by momentarily pressing the control button when non-emergency smoke causes a nuisance alarm. The red light flashes every 10 seconds to remind you that the smoke alarm device has been silenced. The alarm will automatically be reset after 10 minutes, and sound the alarm if particles of combustion are still present.
    If a remote mute function is available, any remote mute feature shall only be used in line of sight of the smoke alarm.

  • Test function: Press the test button periodically to check and confirm the smoke alarm is working normally.

  • Audible and visible alarm signals: Red light will start flashing quickly and the buzzer will start beeping when the detected smoke level reaches the alarm threshold of the Device.

  • Easy Installation: Fixings supplied.

Important safety information

⚠CAUTION! The Device should be installed only by a licensed, qualified electrician. Observe and follow all local and national electrical and building regulations for installation.

⚠CAUTION! Do not remove or disconnect the battery to silence unwanted alarms! This will remove your protection. Open windows or evacuate the air around the smoke alarm device to silence it.

⚠CAUTION! Test the Device weekly to ensure proper operation! The control button accurately tests all smoke alarm functions. Do not use any other test method!

⚠CAUTION! This smoke alarm device is not designed to be the primary protection for buildings that require complete fire alarm systems. Buildings of this type include hotels, motels, dormitories, hospitals, nursing homes, and group homes. This is true even if they were once single-family homes. However, this smoke alarm device may be used inside individual rooms as supplemental protection.

⚠CAUTION! Smoke alarm devices may not alert every household member every time. The alarm buzzer is loud enough to alert individuals of potential danger. However, there may be limiting circumstances where a household member may not hear the alarm (i.e., outdoor or indoor noise, sound sleepers, drug or alcohol usage, the hard of hearing, etc.). If you suspect that this smoke alarm device may not alert a household member, install and maintain special smoke alarm devices. Household members must hear the alarm warning sound and quickly respond to it to reduce the risk of damage, injury, or death that may result from fire. If a household member is hard of hearing, install special smoke alarm devices with lights or vibrating devices to alert occupants.

⚠CAUTION! Smoke alarm devices can sound their alarms only when they detect smoke. Smoke alarm devices detect combustion particles in the air. They do not sense heat, flame, or gas. This smoke alarm device is designed to give an audible warning of a developing fire. However, many fires are fast-burning, explosive, or intentional. Others are caused by carelessness or safety hazards. Smoke may not reach the smoke alarm device quickly enough to ensure a safe escape.

⚠CAUTION! Smoke alarm devices have limitations. This smoke alarm device is not foolproof and is not warranted to protect lives or property from fire. Smoke alarm devices are not a substitute for insurance. Homeowners and renters should insure their lives and property. In addition, the smoke alarm device can fail at any time. For this reason, you must test the smoke alarm device weekly.

⚠CAUTION! The Device is intended for indoor use only!

⚠CAUTION! Protect the Device from dirt and moisture!

⚠CAUTION! Do not use the Device in a damp environment!

⚠CAUTION! Do not paint over the smoke alarm.

⚠CAUTION The smoke detector must not be exposed to excessive heat such as sunshine, fire, or similar.

⚠CAUTION! Do not cover or tape the smoke inlets and buzzer openings!

⚠CAUTION! Do not disassemble or modify the Device!

⚠CAUTION! Do not allow children to play with the device, especially with the control button!

Where to locate

As a minimum, smoke alarm devices should be located between sleeping areas and potential sources of fire such as living rooms and kitchens.

Where to locate Shelly Plus Smoke

⬤ Smoke alarm devices for limited protection
○ Additional smoke alarm devices for better coverage
△ Heat alarms

In single-story homes with one sleeping area, a smoke alarm device should be installed in the hallway, as close as possible to the living accommodation.

To ensure audibility in bedrooms, no smoke alarm device should be further away than 3 m / 10 ft from any bedroom door. It may be necessary to install more than one smoke alarm device, particularly if the hallway is more than 15 m / 49 ft long.
In single-story homes with two separate sleeping areas, a minimum of two smoke alarm devices are required, one outside each sleeping area.

In multilevel or split-level homes, as a minimum, a smoke alarm device should be installed on the ground floor between the staircase and any room in which a fire might start and on each story in circulation areas that form part of the escape route (normally hallways and landings).
Additional alarms should be installed in bedrooms in anticipation of fires originating here, caused by faulty wiring, lights, appliances, smokers, or other hazards.

For best protection, smoke alarm devices should be installed in every room in your home, apart from those listed in the Locations to avoid section. Heat alarms should be used in kitchens, boiler rooms, laundry rooms, garages, and such, where smoke alarm devices would be unsuitable.

Install smoke alarm devices in circulation areas at a distance no greater than 7.5 m / 25 ft from the farthest wall, no greater than 7.5 m / 25 ft from a door to any room in which a fire might start, and no greater than 7.5 m / 25 ft from the next smoke alarm device.

As it is impossible to predict the source of a fire, the best location for an alarm is usually the center of a room or hallway. If it is necessary to place a smoke alarm device on a wall, always locate the detection element of the alarm 15 to 30 cm / 6 to 12 in below the ceiling and the bottom of the alarm above the level of doors and other openings.

In rooms with simple sloped, peaked, or gabled ceilings, install smoke alarm devices on the ceiling 90 cm / 3 ft from the highest point of the ceiling. “Dead-air” at the peak of a ceiling may prevent the smoke from reaching the alarm in time to provide an early warning.

Dear air areas

A: “Dead-air” area

Relocate the unit if it often gives false alarms. See Locations to avoid.

Locations to avoid

  • In areas with turbulent air from fans, heaters, doors, windows, etc., which could draw smoke away from the alarm.

  • In high humidity areas such as bathrooms and shower rooms, or where the temperature exceeds 39 ℃ (100 ℉) or falls below 5 ℃ (40 ℉). High humidity can trigger a nuisance alarm.

  • At the peak of an “A” frame ceiling. “Dead-air” at the top may prevent smoke from reaching the alarm in time to provide early warning.

  • Near objects, such as ceiling decorations, that may obstruct the smoke path to the alarm.

  • In insect-infested areas. Tiny insects may affect performance.

  • In kitchens, boiler rooms, laundry rooms, and garages. Combustion particles from cooking or car exhaust, dust, and moisture could trigger a nuisance alarm.

  • In very dusty or dirty areas. Dirt and dust can build up and impair performance.

  • Within 30 cm / 12 in of light fittings or room corners. In locations that would make routine testing or maintenance hazardous (e.g. over a stairwell).

  • On poorly insulated walls or ceilings.

  • Within 1.5 m / 5 ft of fluorescent light fittings.


⚠CAUTION! Do not use the Device if it has been damaged!

⚠CAUTION! Do not attempt to service or repair the Device yourself!

Package contents

Shelly Plus Smoke package contents

A: 1x mounting bracket
B: 1x smoke alarm
C: 3x anchor plugs
D: 3x screws

Powering the Device

Remove the mounting bracket from the smoke alarm by turning it counterclockwise.

Pull out the plastic isolation tab.

Press and hold the control button for about 3 seconds. Confirm that the LED indication flashes rapidly, and the buzzer emits short loud beeps.

Testing Shelly Plus Smoke


Select an appropriate location and use the mounting bracket to mark the drilling points and punch 3 holes in the mounting surface.

Marking and drilling holes

Insert the 3 anchor plugs in the holes and secure the mounting bracket to the surface with the help of the 3 screws.

Fixing the mounting bracket

Rotate the Device clockwise onto the mounting bracket until you hear a click, indicating that the Device is in place.

Attaching the smoke alarm

Press and hold the control button for about 3 seconds. Confirm that the LED indication flashes rapidly, and the buzzer emits short loud beeps.

Testing Shelly Plus Smoke

False alarm control

The Device features a False Alarm Control, which, when activated, will silence unwanted alarms for up to 10 minutes.

Press and release the control button during an unwanted alarm to silence the alarm buzzer. This will set the Device in False Alarm Control mode.

If the smoke alarm device does not go into False Alarm Control mode and continues to sound its loud alarm signal, or if it initially goes into False Alarm Control mode and then resounds the alarm, the smoke is too heavy and could be a possibly dangerous situation, take emergency action.

⚠CAUTION! If remote silencing function is available, any remote silencing feature shall only be used in line of sight of the smoke alarm.

Battery replacement

When the battery becomes low, the smoke alarm device will beep once every 53 seconds (low battery warning).

You must replace the battery with a new one immediately to continue your protection.

Rotate counterclockwise the Device out of the mounting bracket.

Replace the battery with a new one.

Replacing the battery

⚠CAUTION! Replace only with the same or equivalent type! Danger of explosion if the battery is incorrectly placed.


This unit has been designed to be as maintenance-free as possible, but there are a few simple things you must do to keep it working properly:

Test smoke alarm devices weekly and upon returning from vacation or when no one has been in the household for several days.

⚠CAUTION! The test button accurately tests all functions. Do not use an open flame to test this smoke alarm device. You may ignite and damage the smoke alarm device or your home.

⚠CAUTION! Stand at arm’s length from the smoke alarm device when testing.

The alarm buzzer is quite loud and can be harmful to hearing.

Press and hold the test button for more than 3 seconds to test the alarm.

The alarm will sound loud short beeps.

If the smoke alarm device does not sound, check whether the alarm is properly attached to the mounting bracket.

⚠ATTENTION! Replace the Device 10 years after installation or if the test function does not operate properly!


Clean the smoke alarm device at least once a month.

Gently clean the outside of the smoke alarm device with a soft cloth.

⚠CAUTION! Do not use aggressive detergents!

⚠CAUTION! Do not immerse the Device or wash it under running water!

⚠ATTENTION! If the Device becomes contaminated by excessive dirt, dust, and/or grime, and cannot be cleaned to avoid unwanted alarms, replace the unit immediately.

Visual and audible signals

Normal operation:

  • Red light flash once every 53 seconds

  • No sound


  • 3 red light flashes

  • 3 short beeps


  • Continuous red light flashes

  • Continuous loud beeps

Low battery warning:

  • Red light flash once every 53 seconds

  • Short beep once every 53 seconds


  • Red light flash twice every 53 seconds

  • No sound

Hushed alarm:

  • Red light flash once every 10 seconds

  • No sound (for about 10 minutes)

Hushed low battery warning:

  • Red light flash once every 53 seconds

  • No sound (for about 12 hours)

Control button

  • Press and hold for 3 sec to test the Device.

  • Press briefly to silence an alarm.

  • Press briefly 3 times to put the Device in Setup mode for 2 minutes.

  • Press briefly 5 times to factory reset. The Device stays in Setup mode for 2 minutes.

Inclusion to Shelly Cloud

If you choose to use the Device with the Shelly Cloud mobile application and Shelly Cloud service, instructions on how to connect the Device to the Cloud and control it through the Shelly App can be found in the Shelly Application Guide.

The Shelly Mobile Application and Shelly Cloud service are not conditions for the Device to function properly. This Device can be used stand-alone or with various other home automation platforms and protocols.

Connecting manually to a local Wi-Fi network

Shelly Plus Smoke can be managed and controlled through its embedded web interface. Make sure the Device is in Setup mode, its access point (ShellyPlusSmoke-XXXXXXXXXXXX) is enabled and you are connected to it using a Wi-Fi enabled device. From a web browser open the Device Web Interface by navigating to Press Settings from the Main menu and then the WiFi bar under Network settings.

Enable a Wi-Fi network by checking the corresponding checkbox in the WiFi1 settings and WiFi2 settings (backup network) panels. Select the Wi-Fi network you want to connect the Device to from the NETWORS dropdown menu. Enter the Wi-Fi network password and press the Save settings button in the respective panel. You can also set a static IP by checking the Set static IP and filling in the additional fields below.

The Network SSID, the Device URL, and the connection strength will appear in blue color at the top of the Wi-Fi settings panel when the device is successfully connected to the Wi-Fi network.

Read the complete Shelly Plus Smoke web interface guide.

⚠RECOMMENDATION: For security reasons we recommend disabling or password protecting the Device AP (Networks / Access Point), after the Device successful connection to the local Wi-Fi network.

Disposal & Recycling

This refers to the waste of electrical and electronic equipment. It is applicable in the EU and other countries to collect waste separately.

This symbol on the product or in the accompanying literature indicates that the product should not be disposed of in the daily waste. Shelly Plus Smoke must be recycled to avoid possible damage to the environment or human health from uncontrolled waste disposal and to promote the reuse of materials and resources. It is your responsibility to dispose of the device separately from general household waste it is already unusable.

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