PIR security light doesn't trigger in warm weather!?

[Jimbo]

Hi,

I've got a PIR-triggered security light on the front of my garage. All winter it's worked fine, but with the recent warmer weather it's simply not triggering. It was the same thing last year.

Can anybody offer a reason why it should be affected by average ambient temperature (or could it be a humidity thing)?

Thanks
Jim

 

[holmslaw]

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