Security & Fire Protection Systems/Deactivated alarm is going off


QUESTION: We live in a home that has a deactivated FA215 alarm system, the past few days it keeps going off at various times of the day and night.  When we hit the *Ready button it resets.  Right now the key pad says

FC    AC
Does this mean the main battery needs to be changed?

ANSWER: Hello Deanna, and thanks for your question.

"Deactivated" implies that the system is not active. However, since you're getting a trouble indication at the keypad, I'm assuming that the system is active, but not monitored. Because of that, I have two answers for you.

If the system is active, and you're using it, then yes, the battery needs to be replaced. I can send you information on how to do that if need be.

If you are NOT using the system, then the battery need not be replaced; you only need to remove the AC power to the control by finding and unplugging the system transformer, which will be plugged into a wall outlet near to the control.

Let me know which situation applies, and if you need additional guidance either way, I'll help you work through it.

Best Regards,


---------- FOLLOW-UP ----------

QUESTION: We are not being monitored.  So we would be ok with unplugging it.  My one thought are the smoke detectors, is there any chance they are connected to the main power source?  Thank you for such a quick reply!

Hello again ... yes, it is possible that smoke detectors are connected to the alarm control, and we need to check on that.

There are a few ways we can check, and the easiest way to do that is to power down the alarm control, then test the smoke detectors to see if they sound an alarm.

When I wrote yesterday about just unplugging the transformer, that is half of a power-down. The transformer charges the battery, so in a few hours of unplugging it, the battery will totally discharge. But since we're testing the smoke detectors, I want to completely remove power so that there's no chance that a residual charge that could give us an incorrect test result.

The other half is disconnecting the battery inside the control panel (which is separate from the keypad). So if you have access to the control panel and can open it, just unplug the transformer and the battery. When done, the keypad should be blank.

Next press the test button on any of the smoke detectors. All of the detectors should sound an alarm. To be thorough, repeat this for each of the smoke detectors.

If any of the detectors do not have a test button, they were likely connected to the alarm control. Let me know about that, because we'll likely need to install a new detector.

Please let me know what happens, and if next steps are needed, we'll work through them.

Best Regards,


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Dave Neuweiler


The design and application of burglary and fire systems for homes and businesses. Helping alarm owners understand how their system works. Helping to troubleshoot false alarm problems. Questions about monitoring issues.


Over a quarter century in the industry. Experience in installation, service, and monitoring centers. Training manager for a national protective services company; director of education and training for a national trade organization for for alarm dealers.


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