Interconnected fire alarm woes
Alright, I stuck this in "Hardware" because it is, but it's not PC hardware.
My home has an interconnected fire alarm system. It's turned out to be a nightmare. Periodically, the entire system will false alarm, and I have had to run frantically through the house disconnecting fire alarm units until I locate the offending unit. Disconnecting the unit that triggered the false alarm each time restores the quiet to my house, but this has happened enough times that it's making me consider stop using interconnected alarms and going back to independent units, which is supposedly less safe. However, it would also drive me less insane, since it would be easier to locate false alarming units.
At this point, I've done pretty much everything short of replacing the infrastructure wiring. Over the past year, I have replaced nearly every unit with brand new ones (and in some cases switched from ionization alarms to photoelectric due to some research I dug up on delayed response times on ionization units when there's a smoldering fire), replaced all the batteries in the bunch last week, and even had two of the units replaced under warranty by the manufacturer. Last week we had a false alarm while we were in church, and the neighbors called the fire department. They identified the relatively new CO detector (with a CO reading of zero) to be the culprit and the manufacturer replaced it under warranty.
Today I had another false alarm. The readout on the CO alarm was reading "FIRE" so I felt safe that the CO level in the house is not a danger. When I located the offending unit, it turned out to be one of the most recently replaced units, a photoelectric sensor model. Manufacture date is within an year, and these things are supposed to last ten years. I pulled the battery and it reads 9.44 volts with my multimeter, so the battery is good (it damn well better be, I replaced it last week!) I also put my inductive circuit tester up to the wiring harness that plugs into the fire alarm and it beeped hot, so it doesn't seem like the infrastructure wiring is the problem either. At this point I've had false alarms caused by all three alarm types in the house: ionization, CO, and photoelectric.
Is there anything else you fine folks suggest I might do to troubleshoot root cause on these maddening false alarms?