Vent Axia Ambient Response Humidity Sensor 563550

Vent-Axia Ambient Response 563550 — Self-Programming Humidity Sensor with Pullcord Override, Changeover Relay and Night Setback, 30–90%RH, 220–240V, New Build Residential.

The Vent-Axia 563550 is a wall-mounted self-programming electronic On/Off humidity sensor designed for domestic bathrooms and kitchens. A self-programming electronic On/Off wall-mounted humidity sensor, it reacts to any rapid increase in humidity and temperature by switching a Vent-Axia fan on for rapid removal of moisture-laden air. Unlike simpler fixed set-point sensors, the Ambient Response learns the baseline humidity conditions of the room and responds to rate-of-change rather than a fixed threshold — making it significantly better at detecting genuine moisture-generating events and avoiding nuisance trips in variable ambient conditions. 

Self-Programming — Learns the Room's Baseline

The self-programming capability is the key differentiator of the 563550 over conventional fixed set-point humidity sensors. Rather than triggering at a fixed percentage that must be manually calibrated to the installation, the Ambient Response continuously monitors the ambient humidity level and responds to rapid increases above that baseline — meaning it triggers when a shower or bath is running, not simply because the ambient humidity is elevated on a damp day. This approach eliminates the frustrating nuisance trips and missed triggers that can affect fixed set-point sensors in variable climates.

Night-Time Setback — Prevents Nuisance Tripping Overnight

A night-time relative humidity increment setback feature suppresses nuisance tripping when the humidity level gradually rises as the temperature falls. This is a practical and important feature for bedroom-adjacent bathroom installations — without setback, a fixed set-point or basic rate-of-change sensor can trigger the extract fan in the early hours as ambient temperature drops and relative humidity rises naturally overnight, disturbing occupants. The setback function distinguishes between the gradual humidity rise caused by temperature drop and the rapid rise caused by a genuine moisture event, preventing unnecessary fan operation during sleeping hours.

Pullcord Override, Changeover Relay and Controller Integration

A pullcord provides manual override with an indication light, and the sensor incorporates a changeover relay switch. It can be wired into controller Auto mode connections — integrating directly with compatible Vent-Axia fan controllers without additional relay hardware. The pullcord override allows occupants to trigger the fan manually regardless of measured humidity, with the lamp providing clear confirmation that the override is active. The sensor fits a single gang box for surface mounting and operates from a 220–240V AC supply.

Key Features of the Vent-Axia Ambient Response Humidity Sensor 563550 Include:

• Self-Programming — Learns Room Baseline Humidity and Responds to Rapid Rate-of-Change Rather Than a Fixed Set Point
• Avoids Nuisance Trips — Triggers on Genuine Moisture Events (Showers, Baths) Not Elevated Ambient Humidity on Damp Days
• Night-Time Relative Humidity Setback — Suppresses Nuisance Tripping When Humidity Gradually Rises as Temperature Falls Overnight
• Pullcord Manual Override — Occupant Trigger Regardless of Measured Humidity Level
• Override Indicated by Lamp — Clear Visual Confirmation That Manual Override Is Active
• Changeover Relay Switch — Wirable into Controller Auto Mode Connections Without Additional Relay Hardware
• Operating Range: 30–90% RH
• Fits Single Gang Box — Surface Mounting, Standard Electrical Back Box
• Power Supply: 220–240V AC
• Ambient Operating Temperature: 5°C to 40°C
• Sector: New Build, Residential

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