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PAR-DOORSENSE
Union DoorSense Acoustic Fire Door Hold Open Device
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- CE Marked
- Compliant with BS EN 1155Â
- EMC Tested and rated for timber doors (FD120)
- Incredibly easy to install, no wiring needed
- 2 year guarantee for peace of mindÂ
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Delivery Information
| Delivery Time Frame | Delivery Information |
| Next Working Day By 1PM | When an order is placed by 3pm for next working day on certain items |
| Standard Delivery | Usually delivered in 2 to 4 working days |
| Delivery Charges | |
| UK Mainland | Prices start at £3.95 for very small items, £6.50 for small, £9.50 for medium and £20 for large/long items |
| Scottish Highlands & Islands, Northern Ireland & Ireland | Prices from £30, please see our delivery page for more info. |
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Description
Fire Safety Hardware
Union DoorSense Acoustic Fire Door Hold Open Device
Maintaining clear access routes throughout commercial buildings remains a daily priority for facilities managers, yet the legal necessity to keep fire doors closed can create significant bottlenecks for building occupants. This acoustic hold open device provides a sophisticated solution that allows you to keep high-traffic doors open with confidence because it is engineered to react immediately when an emergency alarm triggers in the vicinity.
The build quality reflects a focus on durability within demanding public environments, where the unit features a curved, fire-retardant casing designed to deflect physical impacts while maintaining a professional appearance. By opting for this hardware, you secure a reliable, battery-operated system that eliminates the need for complex wiring or expensive alterations to your existing electrical infrastructure during the installation process.
194x207x43mm
EXTERNAL DIMENSIONS
2x C Cells
BATTERY REQUIREMENT
Up to 160kg
DOOR WEIGHT CAPACITY
FD120 Rated
TIMBER DOOR FIRE RATING
Why Choose the Union DoorSense Acoustic Fire Door Hold Open Device
This hardware offers a pragmatic approach to fire safety by automating the closure of doors without requiring permanent electrical connections.
Rapid Acoustic Detection
The internal sensors monitor the ambient sound levels of the environment for the distinct frequency of a fire alarm. Once the device hears a signal greater than 80dB that lasts longer than fifteen seconds, it releases the door closure mechanism, which helps to compartmentalise the building before smoke or flames spread through the corridors.
Simple Retrofit Installation
You can mount this unit directly to the door frame with minimal tools because the footprint aligns with many existing fire door retainers on the market. This saves your maintenance team hours of labour, as there is no need to chase cables into the plasterboard or arrange for electrical certification to complete the setup.
Flexible Daily Operation
The integrated timer allows you to program a specific nightly release time, which means the door will close automatically after working hours to maintain building security. This feature ensures that even if a staff member forgets to close a fire door at the end of the shift, the system handles the closure on schedule.
Engineering Quality and Daily Performance
Expertly crafted components ensure that this device remains a dependable part of your building safety strategy for years.
Internal Mechanism and Force Distribution
The internal solenoid is engineered to handle heavy door closers rated between sizes 3 and 7, providing the necessary strength to keep doors weighing up to 160kg in an open position. The hold-open force is distributed efficiently through the mounting plate, which helps to preserve the integrity of the door frame even when the device undergoes constant daily usage.
Engineers have prioritised a fail-safe internal design where the release of the door occurs automatically if the battery levels fall below the operational threshold. This specific design choice ensures that the fire door never remains held open by a flat battery, so your building remains compliant with the necessary fire safety legislation at all times.
Durability and Long-Term Reliability
The external housing uses a fire-retardant material that stands up well to the inevitable knocks from trolley traffic or heavy usage in busy hallways. Its curved geometry is intentional because it sheds impacts rather than absorbing them, which prevents the casing from cracking or deforming when accidental collisions occur during the course of a busy working day.
Maintenance teams will appreciate the clear low-battery indication lights, which give plenty of warning before the power source requires a change. By using standard Alkaline C batteries, the system keeps ongoing maintenance costs remarkably low while providing a high level of performance that you would typically expect from much more expensive, hard-wired alternatives.
Installation and Operational Workflow
Follow these steps to ensure your fire door system meets all legal safety requirements for your premises.
1
Unit Position Assessment
Measure the existing door closer arm to identify the correct mounting point on the frame for the DoorSense unit. Use the provided template to mark your drill holes exactly, as accurate alignment ensures the magnetic engagement plate meets the door closer arm perfectly and operates without any unnecessary mechanical strain on the hardware.
2
Mechanical Fixing
Secure the backplate to the timber door frame using the supplied hardware, checking that the surface is level and that the unit does not obstruct the normal swing of the door. Once the backplate is stable, click the main battery-operated casing into position and test the connection to the closer arm for smooth alignment during operation.
3
Sensitivity Configuration
Set the acoustic sensitivity level according to the background noise of the specific room where you have installed the device. Test the unit by simulating an alarm sound to verify that the release mechanism activates immediately, and then confirm that the door closes fully under the power of the door closer without catching.
Expert Installation and Care Tip
When installing, always check the door closer power setting to ensure it sits within the 3 to 7 range, as this allows the DoorSense to function safely. Keep the unit clean by wiping it with a dry microfibre cloth to prevent dust from interfering with the microphone sensors that detect the fire alarm sound.
Technical Specifications
| Feature | Rating / Standard | Practical Details |
|---|---|---|
| Certifications | CE Marked / BS EN 1155 | This confirms the unit meets UK fire safety standards for holding open fire-rated doors. |
| Fire Door Rating | FD120 (Timber) | Suitable for heavy-duty timber fire doors that require up to 120 minutes of fire resistance. |
| Door Compatibility | Size 3-7 Closers | Designed to work with the standard mechanical closers found in most commercial buildings. |
| Acoustic Activation | >80dB / 15 seconds | Filters out short, loud noises to prevent nuisance releases, activating only for sustained alarms. |
Longevity and Trade Reliability
The two-year guarantee provides peace of mind for site managers who need hardware that performs consistently under daily pressure. This device offers a high return on investment because the combination of simple battery power and hard-wearing construction reduces the need for specialist repair visits over the lifespan of the door.
Compatibility and Fitting Notes
Ensure that your existing door closer is properly adjusted so the door pulls closed fully when the DoorSense is released during an emergency.
The device is specifically designed for indoor use within environments where the ambient noise does not regularly trigger false release events during normal work hours.
Always test the unit after replacing the batteries to confirm the link between the acoustic sensor and the magnetic release mechanism is operating as intended.
Specification
| Manufacturer | Union |
|---|---|
| Finish | Black |
| Guarantee | 2 Year |