Yale false alarms.

[cdbe]

Hi, we've had this alarm for a few years without problems until this week when we've had 2 middle of the night (at different times) false alarms with the same kitchen window DC.

I have a spare DC so I'll change it, but just wondered if it's actually faulty? I had to change quite a few of the batteries in the IR sensors recently (I think it's just that time for them) but none of the DC's have asked for a new battery so I don't think this is related?

Thanks.

 

[JohnD]

It's not well fitted. In that position the shape of the door and architrave mean you need to mount the two parts on blocks for good alignment.

There might be thermal movement of the plastic when it cools at night.

 

[cdbe]

Thanks. I know it's not fitted perfectly, but it's been fine for 2 years. I've swapped the unit now and also changed the battery (even though there was no low battery warning on the panel, the led on the contact did flash when I opened the window?).

 

[secureiam]

John D not convinced its too far apart based on some I have seen working, but your more familiar with these than I am.

as you have swapped the unit out, you'll be able to see how it goes?

 

[JohnD]

I agree, it's just a magnet and a reed switch, and probably it works, but as the installation is not quite perfect, it might be contributing to the problem. I don't know how directional the magnetic field is. There are marks on the sender to show here it should line up with the magnet. Instructions show them fixed parallel, with gap no more than 8mm (or 10mm, instructions say both).

When fitting on curved or moulded architrave and windows, I've built up a flat flatform with a wooden wedge and some filler before screwing into place, to get them lined up. I haven't seen the problem the OP mentions but I don't know if that made the difference.

 

[JohnD]

@cdbe
you could perhaps tinker with the old magnet and the old sensor to see if alignment makes any difference?

The sensor's light should come on when you first move them apart, as it transmits.