Why Does My Doorbell Has 4 Wires Instead of 2 Wires?

Are you trying to install a new 2 wire smart doorbell but your existing doorbell has 4 wires? Here are some questions you might wanna ask – Which wires should you use to connect the new doorbell? what do these 4 wires do? Are these 4 wires are necessary?

Why Does Your Doorbell Have 4 Wires – Two Possibilities Exist

1. Your Doorbell Is A Intercom-Based System

If your doorbell was installed many years ago, then it could possibly be an intercom system that comes with a doorbell instead of a standalone doorbell.

What Do These 4 Wires Do?

What these wires do depends on your intercom wiring and functions. Usually, there are two wires for power and two wires for speakers if your doorbell has 4 wires.

These 4 wires do not always have the same functions for every doorbell with an intercom system, these are the common wire types for doorbells with multiple wires: ground wire, indoor monitor wire, speakers/chime wire, a wire that connects transformer, wire for electric locks.

For people who want to replace an old intercom doorbell with 4 wires with a new doorbell, if you have an existing transformer and a chime at home and you know how they are connected, you need to use a wire from both the transformer and the chime to power your new doorbell.

What if you don’t know which is which? A multimeter will solve your problem. Check the voltage pairing, and there are wires that will give you the 16 to 24 volts, that is what we need.

2. Your Doorbell Has Two Extra Wires

I’ve seen a doorbell with 4 wires while there are two wires unnecessary. If your doorbell button only has two terminals and has no intercom system connected, the doorbell installer might double up 2 wires to act as one.

You can check out the transformer and your chime to see if these two wires are connected to the same terminal as one wire. To install a new wired smart doorbell with two terminals, you don’t have to change anything, you can just connect the existing two wires as one wire to your new doorbell. Or, you can remove the unnecessary wires to install your new doorbell.