Motion detector incompatible with forced air heating?

I’m currently heating primary with a minisplit heat exchanger system. As a simplified description, you can think of this as radiators with fans mounted high on the wall, with vanes that direct the hot air in appropriate directions (usually downward) for mixing when heat is called for.

Unfortunately this seems to be incompatible with Wyse’s IR motion detectors. Those were working fine before the heating system turned on, but now I’m getting false triggers.

I’ve tried relocating the sensors to make sure they aren’t pointed at the heating/blower heads, as instructed in the user’s guide. Unfortunately, the plume of warned air itself seems to be enough to set them off, even at minimum sensitivity. In one case that seems to be happening even with the air escaping through a door into the monitored hallway.

I’m not sure what else I can do except give up on the thermal motion sensors. Which would be really annoying, since five of these cover my house’s critical areas quite well when not heating, and replacing them with other kinds of sensor (cameras, or window and door sensors) would significantly drive up the cost and hassle of this system.

Any suggestions welcome. I’m willing to run any tests which might help diagnose and cure the problem, or share photos/sketches of the installation.

I like wyze’s attempts to find low-cost solutions, but I think this one may just not work in modern temperate-zone housing.

I do have HMS and a motion sensor installed pretty close to my minisplit exchanger.
It is working properly and it never triggered when the heat pump is working.

The sensor is diagonally mounted at 7 feet high on the same wall at about 12 feet from the exchanger.

Wish I knew what’s different about my setups, then. Either it’s the heat pump, or it’s pure random false alarms.

This started being a problem when I changed the set of the heat exchanger’s vanes to direct heat more downward. It’s possible that in your case, and in mine before that change, the airflow was just going over the top of the sensor’s line of sight…

I’m guessing. All I know for sure is that I get false triggers.