Wisualarm Standalone Smoke Alarm

FAQs

What type of fires does the DHI-HY-SA40A detect?

The DHI-HY-SA40A uses split-spectrum photoelectric sensor technology that detects both slow-smoldering fires (such as those from cigarettes or electrical faults) and fast-flaming fires (such as those from flammable liquids or paper). This dual-capability technology uses multiple wavelengths of light to identify different particle sizes in smoke, providing broader fire detection than traditional single-wavelength photoelectric sensors whilst reducing false alarms from non-hazardous sources like cooking vapours and steam.

How long does the battery last and can it be replaced?

The alarm is powered by a sealed 3V CR123A lithium battery designed to last 10 years under normal operating conditions. The battery is non-replaceable by design, as it is permanently sealed within the unit. After 10 years, the entire alarm should be replaced in accordance with manufacturer recommendations and industry best practice. The alarm provides low battery warning signals well in advance of depletion, giving you time to plan for replacement.

What area does one alarm cover?

When installed in spaces with ceiling heights less than 8 metres, a single DHI-HY-SA40A provides protection coverage of 20-40m². The actual coverage depends on room configuration, ceiling height, ventilation patterns and potential obstructions. For comprehensive protection, multiple alarms should be installed according to building layout and relevant regulations. The alarm should be ceiling-mounted in central locations away from corners, doors, windows and ventilation outlets where airflow might affect smoke detection.

How do I silence a nuisance alarm?

The alarm features a combined test and silence button on the unit that can be pressed to silence nuisance alarms for 9 minutes. Additionally, the DHI-HY-SA40A supports infrared remote control silencing, allowing you to silence the alarm from floor level without needing to reach the ceiling-mounted unit. This is particularly useful for installations on high ceilings or hard-to-reach locations. After the 9-minute silence period, the alarm automatically returns to full sensitivity monitoring mode.

What do the different LED indicators mean?

The alarm uses a tri-colour LED system to communicate its operational status. In normal standby mode, a green indicator flashes once per minute confirming the alarm is functioning correctly. When smoke is detected and the alarm activates, a red indicator flashes once per second alongside the audible alarm. If the alarm detects a fault condition (such as sensor problems or low battery), the red indicator flashes twice per minute, prompting you to check the unit or plan for replacement.

Is the DHI-HY-SA40A certified for use in the UK and Europe?

Yes, the alarm is TÜV and CE certified and complies with EN 14604:2005+AC:2008, which is the European standard specifying requirements, test methods and performance criteria for smoke alarms intended for household and residential applications. This certification confirms the alarm meets stringent European requirements for sensitivity, directional dependence, sound output, battery indication and overall reliability, making it suitable for use across the UK and European Union residential markets.

Can this alarm be interconnected with other alarms?

The DHI-HY-SA40A is a standalone unit and does not feature wireless interconnection capability. For applications requiring interconnected alarm systems where one alarm triggering causes all alarms to sound, Wisualarm offers separate wireless interconnected models (such as the DHI-HY-SA40A-R8) that can communicate with compatible Wisualarm devices and optional internet gateways. The standalone model is ideal for single-room protection or situations where interconnection is not required.

Where should I install the alarm in my home?

Install at least one alarm on every level of your home, including basements. Place alarms inside each bedroom and outside all sleeping areas (such as hallways connecting bedrooms). For optimal protection, install additional alarms in living rooms, dining areas and other frequently occupied spaces. Mount the alarm centrally on the ceiling, at least 30cm from walls and corners, and avoid locations near bathrooms, kitchens, garages or areas with high humidity, excessive dust, or strong airflow from ventilation systems, as these can cause false alarms or reduce detection effectiveness.