Therma-vent smoke ventilators

Therma-vent smoke ventilators and automatic smoke vents are designed to reduce smoke build-up, thus providing a safer escape route for occupants, and access for fire-fighting personnel. The system can also be utilised to provide natural ventilation together with smoke extraction.
A typical smoke ventilation system includes Therma-vent smoke ventilators (Opening Vents (OVs) or Automatic Opening Vents (AOVs)) located at the highest point of an escape route staircase or at the top of a smoke shaft. Smoke detectors and manual control points are normally located on each floor. The system can be controlled by a Therma-vent control panel.

 In the event of a fire the smoke detectors on the relevant floor instruct the smoke control panel to operate the Therma-vent AOV creating an upward air flow, venting smoke and toxic gases.

 
The system can be designed to automatically open on receipt of a fire signal or be controlled by the Therma-vent control panel on instruction of the fire services. Alternatively the Therma-vent AOVs can be linked to the Building Management System (BMS) for complete monitoring.

Therma-vent control system

Therma-vent Control Panels supplied as part of a smoke  ventilation system can operate up to four AOVs. Accessories include the Therma-vent Optical Smoke Detector with mounting socket and red LED status indication, the Therma-vent Break Glass and Therma-vent Fireman's Key Switch.

The Therma-vent Control Panel is supplied ready to install with batteries fitted and all internal wiring complete and tested. This enables quick installation times with virtually no scope for wiring errors. It is supplied complete with open, close and reset buttons and LED status indicators behind a break glass panel. The LEDs provide instant status indication, showing any system or wiring faults, system activation and vent position. When used with an AOV the priority control will respond to signals from smoke detectors and manual control points and Fireman’s Switch in order of importance. For natural ventilation the control panel is supplied with a key to remove the break glass to enable operation of the open / close / reset buttons to operate the AOV.
The Therma-vent Control Panel can be installed to operate as a simple centralised ‘stand alone’ system or a larger decentralised or ‘networked’ system with additional Therma-vent Control Panels.

A ‘stand alone’ Therma-vent Control Panel may be installed to operate on the instruction of the fire service. Alternatively it may be installed to operate on receipt of a fire signal from either a smoke detector or manual control point mounted within the fire zone.
This drawing shows a centralised 'stand alone' Therma-vent Smoke Ventilation system installed in an escape route staircase. Manual control points activate the OV.

Please Note - 140 degree option shown

A networked Therma-vent system involves control panels distributed around the building, each controlling a zone with up to four AOVs. This enables cabling distances to be reduced.
Networking requires the installation of a Therma-vent Control Panel within each fire zone. These can be linked to the central control zone utilising Fireman’s Switch control points.
Individual zones activated by smoke detectors or manual control points can be overridden by the centrally mounted Fireman’s Switches.
Alternatively the Therma-vent Control Panel can be installed as part of a larger system receiving signals from a BMS via its ‘no voltage’ monitoring capacity. 
Networked Therma-vent Smoke Ventilation system installed in living accommodation, escape route staircase and smoke shaft. Smoke detectors and manual control points activate the AOV. Fireman's switches enable central control.

Please Note - 140 degree option shown

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