How To Replace A Doorbell Transformer

In this video blog post we teach you how to replace a doorbell transformer. If you are planning on installing a smart doorbell like the Ring Pro or Nest Hello you might need to replace your doorbell transformer to provide enough voltage for your new smart doorbell. We’ve also included the step by step instructions on how to replace your doorbell below.

Why Replace A Doorbell Transformer?

You might also need to replace your doorbell transformer if your existing doorbell is not working and your doorbell transformer has burnt out. The instructions below are how to replace a doorbell transformer for a Ring Doorbell or Nest Doorbell but they will also work for standard non smart doorbells as well.

What Doorbell Transformer Should You Use?

Typically transformers that put out 16V -24V will provide enough power for both the Ring and Nest smart doorbells. I recommend using this 16V transformer for Ring doorbell and this 16V transformer for Nest Doorbell. I’ve tested both these transformers and they will work with smart doorbells and non smart doorbells on the market.

Other Things To Know Before You Get Started.

If you are having issues with your doorbell or smart doorbell I recommend you take a look at our doorbell troubleshooting guide first to determine what’s wrong with your doorbell.

We also have another video which will teach you how to test your existing doorbell transformer voltage to determine if you have enough voltage for your smart doorbell. You can find this video on how to test your doorbell transformer here.

If you want to know what doorbell chimes we recommend we’ve included a list of doorbell chimes that will work with each type of type of smart doorbell below.

List Of Doorbell Chimes That Work With Ring Doorbells

List Of Doorbell Chimes That Work With Nest Doorbells

Recommended Doorbell Transformer for all doorbells Including Ring Doorbell & Nest Hello Doorbell

How To Replace A Doorbell Transformer

The instructions below will guide you through step by step instructions on how to replace a doorbell transformer. The procedure is the same for replacing a doorbell transformer for nest, ring or a standard doorbell.

Step 1: Locate your doorbell transformer. If you don’t know where it is this guide on where to find your doorbell transformer can help.

Step 2: Once you’ve located your doorbell transformer turn off the at the circuit breaker that provides power to the doorbell transformer. If you don’t know which circuit breaker it is just turn all of them off.

Turn Off Power To Doorbell Transformer at circuit breaker

Turn Off Power To Doorbell Transformer at circuit breaker

Step 3: Disconnect the doorbell wires wired to the two terminals on the doorbell transformer surface. Access the transformer wiring by opening up the junction box the transformer and wiring is mounted on.

Step 4: With the junction box wire removed take a picture so you can see how the existing doorbell transformer was wired.

Step 5: Disconnect the existing transformer wiring by un twisting the wire nuts on the transformer wiring in the junction box.

Disconnect existing transformer from existing wiring.

Disconnect existing transformer from existing wiring.

Step 6: Remove the doorbell transformer. The doorbell transformer is typically secured to the junction box with plastic or metal nut on the inside of the junction box that holds the transformer tight to the junction box. From inside the junction box you can unscrew this thin nut pull it over the wiring for the transformer and then remove the existing transformer.

Step 7: Insert the new doorbell transformer into the old hole in the junction box where the transformer was located. Remove the plastic nut that typically comes attached to the transformer before inserting it into the junction box. Pull the wires though the junction box hole then attach the transformer and secure with the nut that comes with the transformer.

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Step 8: Wire the new transformer to the existing wiring in the junction box. Refer to the picture you took from earlier if needed. If you don’t have a picture typically a doorbell is wired with the black wires to the black wires which are also known as the hot wires, the white wires to the white wires which are known as neutral wires. And the green wire to the green wires or bare metal which are known as ground wires. If you don’t have a ground wire, ground the transformer to the metal junction box.

Wire the new doorbell transformer with wire nuts to the wiring in the junction box. Green wire to green wire, black to black and white to white.

Wire the new doorbell transformer with wire nuts to the wiring in the junction box. Green wire to green wire, black to black and white to white.

Step 9: Reinstall the junction box cover.

Secure the doorbell transformer junction box cover.

Secure the doorbell transformer junction box cover.

Step 10: With the junction box cover installed re-connect the doorbell wires to the new transformer wiring terminals. It does not matter which color wire you connect to each terminal on the doorbell transformer as long as you have connected both of them.

Wire the doorbell wires to the new doorbell transformer.

Wire the doorbell wires to the new doorbell transformer.

Step 11: Check your work and turn the power back on at the circuit breaker. Your job is now complete.

How To Replace A Doorbell Transformer Summary:

Replacing your doorbell transformer can take anywhere from 15 minutes to an hour depending on your skill level. The most important thing to remember is to turn off the power before you get started working on your doorbell transformer. If you’re having trouble finding your doorbell transformer make sure you thoroughly search mechanical rooms, basements, attics and garages. I’ve often found them tucked into corners or mounted on the ceiling where you wouldn’t expect them.

Doorbell transformers step down the voltage from a higher 120V which is used for typical house wiring to a lower safer voltage of 16-24V which is typically used for low voltage electronics like doorbells.

I recommend using this doorbell transformer from Maxdot because I have throughly tested it and it has reliably worked with all standard and smart doorbells I have tested. It’s important to note that this doorbell transformer puts out more amperage than standard transformers which makes it better for smart doorbells it is a 16V - 30VA transformer which is what is recommended by smart doorbell manufacturers.