How to Stop an Old Alarm System from Continuously Beeping

Tired of that annoying beeping sound?

We don’t blame you! We’ll help you troubleshoot this frustrating problem.

The first thing you’ll want to do is go to your alarm keypad. If you know the code to disarm the alarm, enter it and see if that stops the beeping sound. If you don’t know the code, look for buttons labeled “clear” or “reset” and press those.

Note: You can also try pressing the “*” or “#” keys, as these buttons often silence the keypad sounder. However, DO NOT press those keys simultaneously because on many systems that combination is used as an emergency signal to dispatch police.

If the beeping sound persists or starts again shortly after you put in your code, you may have one of the following issues:

  • Loss of power
  • Low or dead backup battery
  • Phone line connection issue

Let’s look at how to troubleshoot each of those problems below.


Want a security professional to stop the beeping sound? We’re happy to help. Feel free to call us at 804.745.1117 or schedule an appointment by clicking the button below.

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Problem #1: Loss of power

Alarm systems need electricity for everyday operation, so if your alarm isn’t getting any power, it will alert you to let you know something is wrong.

Sometimes alarm keypads will display a “AC loss” or “No AC” signal if it’s lost electrical current. If this is the case, the beeping noise is meant to alert you that your system is now running on backup power (typically, this will be batteries).

If you notice that other appliances or electrical fixtures in your home aren’t turning on, that could confirm you have this issue.

Solution: Check the transformer

Security System Transformer

Most security system transformers will look something like this.

Every alarm system has a transformer that plugs the security system into a standard AC wall outlet for power (see above).

If that transformer/outlet connection is loose, though, your system will lose power (and start beeping to let you know). Check that the transformer is securely connected to the wall outlet.

If the connection is secure, the outlet itself may be faulty or the circuit breaker it lives on may be tripped. You’ll need to contact a professional to determine what the issue is and resolve it.

Problem #2: Low or dead backup battery

Most alarm systems have a backup battery that kicks in if the power ever goes out. When the battery is low or dead in an old alarm system, the system will start beeping to alert you that it needs to be replaced.

If your battery is low, it will either need to be disconnected or replaced. If you don’t use your old alarm system anymore, we would recommend disconnecting the battery and terminal so the beeping sound doesn’t come back.

Solution: Replace or remove battery

Follow these steps to replace or remove your battery:

Step #1: Locate the alarm control panel

The control panel is usually located in a closet, utility room or basement. Look for a putty-colored, rectangular box with the alarm manufacturer’s name on it.

Step #2: Open the control panel

To open the panel, try opening it with a screwdriver. Some panels require a key or security code to be opened. Check the top of the box for a taped key. If you don’t have the key or don’t know the code, you’ll need to contact a professional to help you disassemble the panel and remove the battery.

Step #3: Identify the battery

If you can remove the panel yourself, you’ll see a small, black, square-shaped box connected to a circuit board. This is the battery. If you are replacing the battery, take note of what type of battery it is so you can purchase a replacement.

Step #4: Disconnect the battery from the circuit board

You’ll see two wires connecting the battery to the circuit board. Start by gently removing the black wire from the negative terminal on the battery. Next, remove the red wire from the positive terminal.

Safety tip: Be careful that no metal objects touch the battery terminals or wire connectors.

Now that the battery is removed, you can reconnect a new battery or leave your system disconnected.

To reconnect a new battery, do the following

Once you have a replacement battery, you can reconnect it to the circuit board starting with the red wire (positive terminal). Then, reconnect the black wire (negative terminal) to the battery.

After the battery is connected, go to your alarm keypad and see if that got rid of the low battery notification. If the warning persists, you’ll need to contact a security system professional for further troubleshooting. This may not be an instant fix, please allow up to 6 hours for the panel to recognize battery change.

To leave the system disconnected, unplug the transformer

If you choose to leave the old alarm system disconnected, you’ll also want to unplug the transformer. (see image above of transformer). If you unplug the transformer, your alarm system will no longer receive power and that should stop the beeping sound for good.

Problem #3: Phone line connection issue

Landline Phone and Alarm System

A problem with your landline could be what’s causing your alarm to beep.

If you have a monitored security system and use landline monitoring (vs cellular monitoring), it could be beeping due to a connection issue with the phone line. The simple way to confirm a phone line issue is to pick up the phone. If the line is dead, this is your issue.

Solution: Contact a professional for assistance

Since fixing a faulty phone line can be complicated, we recommend contacting a security professional to help you troubleshoot the connection issue. You may need to also contact your phone service provider to see if the issue is something on their end.

Keep in mind that landline monitoring is a less secure way to keep your home monitored. That said, your safest option is to have a professional upgrade your security system to cellular monitoring instead of simply repairing an outdated system.

Still hear the beeping noise? Contact a Virginia security expert for help

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If you’ve tried troubleshooting the problem but still hear that annoying beeping sound, it’s time to contact a professional. With over 70 years of experience, we know how to fix any type of beeping alarm system—old or new.

Interested in a new alarm system for your home? Visit our home alarm systems page for more information about the systems we install.