Best answer:

Answer by frozenbrew
Maybe the button has a normally closed contact which opens when pressed

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Even a novice electrician or a complete newbie to wires and circuits can install a new  doorbell or repair an existing one. Yet most people are apprehensive about handling doorbells and often hand the task over to a professional electrician. Others settle for the safer and easier option of replacing the wired doorbell installation for a wireless one that is easier to install and use. Not that it is a bad choice, but isn’t it sad that you have to invest in a wireless doorbell purely because you chickened out at the thought of handling a few screws and wires? This page is aimed at giving you comprehensive and concrete information about doorbells, transformers, wires, batteries and everything in between.

You will also find complete information with diagrams on

1. How to Install a Wireless Doorbell
2. How to install a wired doorbell
   • Wiring for buttons on both front and back doors
   • Wiring for a doorbell on the front door and a buzzer on the back door
   • Wiring for a combination of a bell and a buzzer
   • Wiring for Door Chimes

3.   Troubleshooting your doorbell

Basic Information: Doorbell Circuit

The doorbell as I mentioned earlier, is one of the simplest yet coolest devices ever created. We live in a world of gizmos and gadgets. We have gadgets that can control everything from the sound of music to the temperature in our home all at the snap of fingers. And here is a device that does nothing but create some kind of noise when a button is pressed. Isn’t that primitive? Not quite. A doorbell works on the very basic principle of electromagnetism and converts it into buzzes, chimes or rings. At the core of a doorbell lie a transformer and an electromagnet (a magnetic device with coiled wire around it). When you press the button of a doorbell, it completes an electrical circuit. Electricity flows through the electromagnet via the transformer. This electricity then activates the magnetic field which is used to trigger some sort of noise making apparatus (differs from one model to the other). Most doorbells and buzzers today run on 16V whereas earlier models used to operate on 10V.

Transformer

The transformer is a tiny device enclosed within the doorbell in newer models and separate in older models. It reduces normal household electric current from 120V to 10 or 16 V as per the requirement of the bell or chime. Usually, all transformers have two permanent wires, one black and the other one white which is used to provide power to the unit from the source. The opposite side of the transformer has two attachment screws which can be used to connect the low voltage wires to it. It is these wires which are in turn connected to the electric bell. Transformers are relatively compact and are designed in such a way that they can be installed directly into an outlet or a junction box.

• However, always ensure that you follow the rules of safety before trying to install any electrical appliance.
• Switch off the power before you handle any wiring to avoid an electric shock.
• Ensure that you run the wires along the wall using supports wherever necessary.
• Always use insulated staples to handle any electrical wires.
• Use electrical insulation tape to cover any exposed ends of the wire. Never ever use ordinary tapes to cover electric wires or leave the wires exposed.

So, are you all set to begin?

Mounting the bell and the receiver

Mounting the doorbell button and the receiver unit should be easy. However, I am mentioning it because I do not wish to omit any part from the installation.

1. The first step is to identify the right position for both the doorbell button as well as the receiver. The button should be positioned at an ideal height so that each family member should be able to ring it comfortably without having to stand on the toes or bend down. The receiver on the other hand should be placed in a position so that it is audible throughout the house. If the wall has a drywall finish, then you will have to use toggles or molly bolts to anchor it.
2. You will need a Power drill and 3/8-inch bit, Insulated screwdrivers, insulated Pliers and a stepladder to complete mounting the doorbell button and the receiver.  

The single button doorbell

The single button doorbell is probably the simplest of them all. However, it can rarely be found today as most home owners prefer to use door bells or door chimes that have multiple buttons (for the front and back door). Here are the steps to complete the installation.

1. Connect one wire to the terminal screw on the button of the doorbell. This wire should run straight (uninterrupted) to the terminal screw on the transformer.
2. Connect the second wire to the second screw on the button and the other end of this wire should be connected to the terminal screw on the bell.
3. The third and last wire will run from the terminal screw on the bell to the other screw on the transformer.

That’s it. You have completed installing a one button wired doorbell. Test the doorbell.

Wiring for buttons on both front and back doors

The procedure for mounting the doorbell buttons and receivers are still the same. The only difference being that you will have to mount the button at two different places now.

• Connect one wire to the terminal screws on either buttons (front and back door) and connect the other end of both these wires to one of the terminal screws on the transformer. (Running the wiring here can be slightly tricky. Ensure that you have a proper plan chalked out on paper before you begin)
• Connect the second wire to the second terminal screws on either buttons and connect the end of these wires to the terminal screw on the bell.
• Now connect the third wire to the remaining terminal screw of the wire and the other end to the second terminal screw on the transformer.

That’s it. However, please be informed that in this type of a doorbell, both the buttons will activate the same bell sound or chime.

Wiring for a doorbell on the front door and a buzzer on the back door

Now let’s get into slightly more advanced installations. In the earlier example, we noticed how we can connect two buttons to the same doorbell. However, since they activate the same sound, it becomes a tad difficult to point out the exact door that the visitor is at. So, to solve the problem you can install a buzzer for the back door and a doorbell for the front door (This installation is not for the buzzer-bell combination model). Sounds difficult? It isn’t.

• Connect one terminal screw of either buttons and connect the other end of these wires to one terminal screw on the transformer.
• Connect the second terminal screw of the front door button and connect it to one terminal screw on the doorbell.
• Connect the second terminal screw of the back door button and connect it to one terminal screw of the buzzer.
• Connect the second terminal screw of the buzzer to the second terminal screw on the doorbell. Yes, the two units are connected.
• So far so good. Now here comes the tricky part. Connect a wire to the same terminal screw on the doorbell (which is connected to the buzzer) and connect the other end to the remaining terminal screw on the transformer.

That’s it. This installation is ideal if you already have either one of these devices installed and wish to add the second one. However, if you are planning fresh installations then you can opt for the bell-buzzer combo device to reduce costs.

Installing a door chime

Most homes will have a door chime and not the vintage bells and buzzers. However, their wirings are pretty much the same. One thing that you need to ensure (if you are installing a separate transformer) is that the transformer matches the voltage requirements of the chime. If the transformer is built in the chime unit, then installation becomes a cinch.

• The steps for mounting the doorbell button and the receiver are similar to that mentioned in the wired doorbell installation techniques. You always have an easier option of using double sided adhesive tape to mount it.
• If you are replacing an old wired doorbell installation with a wireless one, then you will have to remove the old button from the door and cover any exposed wires with electrical tape. (Follow safety rules mentioned here) You can also choose to bundle all covered wires together with electrical tape.
• Install the new wireless doorbell button at a comfortable height on the door. (Over the same hole in case of a replacement installation)
• Place the receiver at an ideal location inside the house. Always ensure that you keep it within the operation range of the unit to obtain maximum volume and resonance. Most people prefer installing the receiver in the hallway.
• If it is a plug-in model then the receiver has to be plugged in an electrical outlet. If it is a battery powered model on the other hand, then put in the batteries before installation.

Testing the installation

While the doorbell can be tested by simply pressing the button at the front door, that might not be sufficient. Press the button and have someone move from room to room in the house. This will give you a good idea about the places where the sound is least audible. You can always purchase additional receivers to place at different locations in the house (Ideal for multi floor homes). If there is no sound, then either the unit might be faulty or the batteries might need to be replaced. Wireless doorbells might ring for no reason whatsoever. If this is the case, then it is being caused by external interference like garage doors, car alarms. However, there are advanced wireless doorbell models which have built in support to block out external frequencies.

That’s it. Isn’t that easier as compared to installing wired doorbells? You can actually complete installation and testing in less than 10 minutes. So when are you planning to replace your old wired doorbell installation?

Symptom 1: The chime doesn’t sound

Step1: When the chime doesn’t sound, the first and most obvious thing to check in a wireless doorbell unit will be the batteries. Check the batteries in both the push button and the chime unit. Push buttons that have add on features like a flash light or a warm glow light can run out of juice very fast. Replace the batteries and check the unit again. If it works, then you can keep replacement batteries with you. You can also opt for a plug in unit as it saves you from the hassle of frequent battery replacements. If it still doesn’t ring, then it is time to move on to step 2.

Step 2: Most regular wireless doorbell models have a frequency limit or 75 to 150 feet. This range is ideal for small homes. However, if you live in a large home, then there are chances that you might have accidentally installed the receiver beyond the maximum allowed frequency range. The best way to find this is to shift the receiver to a place that is closer to the doorbell button. Does the chime unit sound now? If yes, then you can permanently mount the receiver at the new location. At times, you need to try different locations for your receiver in order to find the spot that gives you maximum signal strength and clarity. The angle at which the receiver is installed can also affect the signal quality. Have you heard about long range wireless doorbell systems for your home? These systems have a range of up to 300 feet or more. You can also buy an ‘add on’ amplifier or extender for your doorbell system. If the doorbell doesn’t ring despite moving the receiver around, then let’s move to step 3.

Step 3: If you have installed the receiver within the frequency limits specified by the manufacturer and the chime unit still doesn’t sound, then the button might be experiencing interference from metal surfaces. Yes, the presence of metal frames or grills often reduces the transmission range in doorbell buttons. If you have mounted the doorbell button on a metal surface or close to it, then you can use wooden shims to separate it from the surface.

Step 4: If you have sweat-ed it out this far but have been unable to locate the problem, then you might need to replace the doorbell unit. At times, people install the doorbell unit outside the home in extreme weather conditions that can disrupt its working or damage it completely. Ensure that you buy only the best quality wireless doorbells that last long and offer quality performance.

Symptom 2: A doorbell that rings randomly

This is an extremely common symptom in wireless doorbells. It occurs because of interference from other frequencies. Garage door alarms, car clickers, other wireless doorbells or similar devices can trigger off wireless doorbells. Imagine running down all the way from your study, only to find that the doorbell was triggered by the vacuum cleaner. Isn’t that frustrating? However, the best way to address this problem is to buy a higher end model that supports multiple wireless frequencies. Some popular wireless doorbell models have up to 32 different built in frequencies that block most external frequencies and save you a lot of unwanted trouble.

Points to remember

• The doorbell is one of the simplest devices that have ever been created. The circuitry is extremely simple but there are four different components that make it function. You need to identify the source of the glitch and then proceed accordingly.
• Troubleshooting is eliminating one step at a time in a precise and organized manner. The steps can vary from very easy to advanced. It all depends on your expertise with electrical devices and the kind of tools that you have with you. Do not attempt anything that you are uncomfortable with.
• You will need basic tools like screwdrivers, clamps and needle nose pliers. There are some other optional tools as well like a voltmeter, a continuity tester.
• Doorbells are low voltage electrical devices and you can troubleshoot them without shutting off the main electric supply or circuit breaker. However, if you are going to test the transformer (a component of the doorbell circuit that converts 110V electricity to 10 or 12 Volts), then it is recommended that you switch off the power before you begin.  The irony of the situation though is that you need to have the power switched on to test most components. So you will have to keep switching it off and on after each step. Always respect electricity and you will avoid any unpleasant incidents.