Doorbell doesn’t work? Checking a doorbell transformer is easy—if you can find it. Sometimes locating it can be the real challenge. Here is where to look and what to do.

Sometimes finding a doorbell transformer is a challenge because the transformer is tucked out of view. It may be located inside the doorbell’s chimes or bell enclosure but often is located elsewhere.

Internal diagram of a wiring system on a regular household doorbell.
A conventional doorbell has wires that connect the chimes or bell to the transformer, which reduces standard voltage to low voltage.

If you know where the doorbell wires run, trace them back to find the transformer’s location. Note: Newer homes often have doorbell transformers conveniently located in plain sight, high on a garage wall.


If you can’t find the doorbell transformer, check these places:

• A floor joist in the basement

• Below the doorbell chimes or bell

• In a nearby closet (perhaps the entry closet)

• In the attic. If in the attic, it may be buried under insulation)

• In a crawlspace

• Inside an electrical box near the electrical panel or the doorbell

When you find it, note the proper voltage rating. This should be stamped on the transformer and/or the doorbell mechanism.

To test the doorbell transformer:

1 Adjust a volt-ohm meter’s scale to 25 VAC. Touch the probes to the two flat screws that connect the small-gauge doorbell wires to the transformer.

2 Test the transformer by comparing the reading to the device’s voltage requirements. If it’s too low or exceeds 16 volts, shut off the power to the transformer before doing any more work on the doorbell system. Replace the transformer with a new one, readily available at home centers.

For more, see Doorbell Does Not Ring — How to Fix a Doorbell.

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About Don Vandervort
Don Vandervort has developed his expertise for more than 30 years as a remodeler and builder, Building Editor for Sunset Books, Senior Editor at Home Magazine, author of more than 30 home improvement books, and writer of countless magazine articles. He appeared for 3 seasons on HGTV’s “The Fix,” and served as MSN’s home expert for several years. Don founded HomeTips in 1996. Read more about Don Vandervort