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Pro tip: check those old door sensor magnets before you trust them
Had a call back yesterday on a system I installed 6 months ago in a house near Oak Park. Turned out the magnet in the door frame had lost its pull strength and the sensor wasn't closing the circuit right, even though it looked fine. Anyone else run into magnets degrading like that over time?
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brian_hart3mo ago
Had a rusty one on a garage door last year @beng51 that looked fine visually but the magnet was pulling less than half the strength it should. Took me forever to track down because the contacts were clean and the gap was perfect. I always test with a spare reed switch now or hold a known good magnet next to it to compare.
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beng513mo ago
Huh, I don't know if I'd call that a widespread issue. I've been doing this for years and never once had a magnet go bad like that.
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morganl713mo ago
30 years in the trade and I would have agreed with you until about 2018. Had a customer call me out for a false alarm on a cheap magnetic contact that was maybe 5 years old. Magnet looked perfect, no rust, no cracks, but it was maybe 60% as strong as a brand new one. Pulled it off and tested with a spare reed and sure enough the magnet was the problem. Now I keep a handful of known good magnets in my truck just for that exact test. Never would have believed it if I hadn't seen it myself.
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