Why Is My Refrigerator Making a Loud Buzzing Noise?

What's normal and what isn't

A refrigerator makes some sound when it runs: a low hum from the compressor, a fan whooshing, the occasional click and gurgle as it cycles. What's worth paying attention to is a change. A new buzz, a sound that's much louder than before, or one that's constant and harsh is a sign something is working harder than it should or is loose or worn.

The usual suspects

• Dust on the condenser coils. Coils covered in dust and pet hair can't release heat well, so the compressor and fan run longer and louder. Cleaning the coils is one of the few fridge jobs that's safe to do yourself with the fridge unplugged.
• A failing condenser or evaporator fan motor. A fan motor with worn bearings or something touching the blade can buzz, rattle, or squeal. Noise that gets louder when the compressor kicks on often points to the condenser fan, near the bottom back. Noise from inside the freezer often points to the evaporator fan.
• Ice on the evaporator fan. Frost build-up from a defrost problem can let the fan blade hit ice, producing a buzz or scraping sound that stops when the door is opened or the ice melts.
• The compressor or its start components. A compressor that is struggling can hum or buzz loudly, sometimes followed by a click as it shuts off, and the fridge may stop cooling well. This is the one that tends to be expensive, so it is worth confirming the cause before assuming it.
• The ice maker's water valve. A buzz when the ice maker fills, or when the fridge is not in use for the ice maker, can come from the water inlet valve, especially if the water supply is turned off or low.
• Vibration. A fridge that isn't level, or one touching a wall, cabinet, or the floor in a way that carries sound, can seem to buzz when it's really just the vibration transferred.

Clues that narrow it down

• When it happens. Only when the compressor runs? Only when the ice maker fills? Only after a defrost cycle?
• Where it comes from. Bottom back is usually the compressor and condenser fan. Inside the freezer is usually the evaporator fan. The back of the fridge near the water line is the water valve.
• Whether it stops with the door open. Many fridges shut off the evaporator fan when the door opens. If the noise stops, the fan is the likely source.
• Whether cooling has changed. A noisy fridge that's still cold is a different situation than a noisy fridge that is warming up.

What you can safely do

Unplug the fridge and clean dust from the coils with a vacuum and a soft brush. Check that it's level and not touching the wall or cabinets. Move anything off the back of the fridge that could be rattling. Don't remove interior panels or chip away ice near the evaporator; the refrigerant lines run right behind it.

When to call for a repair

If the buzzing continues after cleaning the coils, if the fridge is getting warm, if the noise comes with clicking and the compressor keeps starting and stopping, or if there's ice building up in the freezer, have it looked at soon. A noisy fan is a small repair; a struggling compressor left running can turn into a bigger one. We'll find the source before recommending anything.