PIR sensor false alerts

I have two PIR sensors that trigger on water movement and light changes. It would be good if they worked like normal driveway lights with PIRs. They do trigger on people movement but are useless if we get 99% alerts that are false!

They were meant to replace the turned off alerting of the motion triggered by 2 cameras but those are too sensitive or lack the complexity to correctly trigger on people.

So it seems like Wyze needs to revisit real world scenarios on their cameras and PIR sensors.

1 Like

If these are detecting water movement, does that mean they are mounted outside?


They’re not intended to be used outside, so I’m not surprised you’re running into issues. Any PIR sensors just detect heat changes, so water makes sense. Light shouldn’t affect it, per se, but SOURCES of light often give off heat. For example, if you were to stand behind the sensor and shine a bright, hot light into its field of view, it shouldn’t react at all. But if the bright, hot light, is in front of the sensor, it may react to the heat that the light is emitting.


If used outdoors, the sensors need to be shielded from seeing cars on the street, people on the sidewalk, and nearby pets and children. They cannot be directly exposed to rain – they are an indoor device, and I’m reasonably sure water on the lens would create a trigger.

I personally have two motion sensors mounted outdoors, though. One looks at my front porch and about half my driveway, and one looks at my back yard. I get maybe 1 false trigger a day on the driveway sensor, and maybe 1 or 2 on the backyard sensor.

The driveway sensor is most often false triggered by a cat that wanders across the front porch in the evening, and sometimes during the day by birds looking for spider webs on the side of my house. The backyard sensor is most often false triggered by a bird or squirrel in the backyard. Nether have ever been triggered by rain, although I suppose you could live in a hotter area where rain comes down much cooler than the environment, or have the sensor directly exposed to weather.

My sensors always trigger on any people, cars, or lawn mowers within their view. I shield my driveway sensor from a view of the street or people on neighborhood sidewalks by using an overhang. That overhang also shields it from direct exposure to weather. I shield it from views of my neighbor’s pets and children by turning it about 30 degrees away from their house.

So I would recommend reviewing whether your sensors are exposed to weather, and exactly what they can see. A large heat object like a car can be seen much further away than a human, so be sure your sensor is shielded from street views, and of course any direct exposure to weather.


I have two on community covered patio/pool house and it triggers on water movements. There are lights with pir sensors that aim directly at water and do not trigger. If they sense heat they need better logic to not trigger on false alerts.

They are inside of a building that has water under it. Enclosed area. Still seem too sensitive unlike standard driveway motion lights (with PIR sensors).

They’re definitely pretty sensitive, because they’re tuned for indoor use. In a normal indoor scenario, there’s not much that should give you a false positive, but a covered patio, especially one with a pool, wouldn’t be as predictable with heat changes as a true indoor setting. I’m not sure whether the lack of adjustable sensitivity is a hardware limitation or not, but if it’s possible, I agree it would be nice.

As a jerry-rig solution, you can try covering the lens with some scotch tape or saran wrap or something semi-transparent like that. If one layer is still too sensitive, you can add another. It should reduce the sensitivity without totally impairing it.

Just a thought. These Wyze PIR sensor seems to be tuned/optimized for a animal/mammal detection. If it works occasionally for detecting other movements by objects its may be an unintentional “bonus” and inconstant.

Nerdland has a good idea, which appears to re-tune the detection by physical alterations by trial and error.

Background if interested
Passive infrared sensor (PIR sensor) the sensor converts the resulting change in the incoming infrared radiation into a change in the output voltage, and a detection.

PIR-based tuned for motion detection is used to sense movement of people, animals, or other objects which has changes in the amount of infrared radiation impinging upon it, which varies depending on the temperature and surface characteristics.

Used in a mailbox, is brilliant, as the door opening changes the low-energy internal environment, into a high-energy zone by flooding the sensor with sun energy.

In the case of water detection, it depends on the environment, if the ground and the water are emitting similar amounts of energy, these low-cost sensors may not works so well. If the ground and flowing water had a large delta-T. then it could reliability detect flooding. Most flood detection devices use conductivity changes for leak detection. Some expensive and very reliable solutions use a hybrid of detection methods. No mainstream commercial product is based solely on PIR.

1 Like