Thanks for the quick reply. I took the sensor down due to the problems. One kept reporting the window was being opened. The other seemed ok but then apparently reported to the panel the window was open and it bypassed it when arming. They were just not reliable.
I suspected a better y problem but just thought the battery was old and weak.
The magnet must be aligned parallel with the correct side and correct spot where the reed switch is. The sensor cannot properly close when the magnet is not aligned with the right location. There is a small symbol on the side of the housing which indicates where the reed switch is and where the magnet must go.
No worries, the drawings in the manufacturer manual showing the magnet alignment aren’t to scale and they don’t even place the arrow mark in the spot its actually found on the housing. It could certainly be improved.