Read the guide: Vibration frequency explained
How to test your refrigerator
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Step 1: Wait until the compressor is running. You'll hear a steady hum, usually from the bottom back. If it's quiet, wait a few minutes; it turns on and off by itself.
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Step 2: Clear the top of the fridge and place your phone flat, screen up, near the front. Use a sturdy step stool if you need one.
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Step 3: Keep the doors closed. Tap Start (on iPhone, tap Allow) and keep your hands off the fridge while it measures for 30 seconds.
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Step 4: Read the strength label. If the result says the vibration may be faster than your phone can measure, that's expected on a fridge. Go by the strength.
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Step 5: Test again once the compressor has stopped. If the reading barely changes, the shake isn't coming from the compressor.
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Step 6: Save an image of the result to compare after a fix or to show a repair person.
What your result means
Your result lands on one of four levels. This page uses the machines and appliances scale, which is based on RMS velocity in millimeters per second (mm/s).
| Level | Range (RMS velocity) | What to do |
|---|---|---|
| Smooth | Under 0.71 mm/s under 0.028 in/s | Your fridge is running quietly. Any hum you hear is normal compressor and fan noise. |
| Normal | 0.71 to 1.8 mm/s 0.028 to 0.071 in/s | Normal for a running fridge. A light buzz you can feel on top is expected. |
| Rough, check it | 1.8 to 4.5 mm/s 0.071 to 0.177 in/s | More shake than a fridge usually has. Check that it's level, resting on its front legs and not just its rollers, and not touching the wall or cabinets. Then test again. |
| Too much vibration | 4.5 mm/s or more 0.177 in/s or more | Too much vibration. Make sure the fridge doesn't rock and nothing on top or behind it is rattling. If it knocks, bangs or stops cooling, call a repair person. |
Reading a refrigerator vibration result
Most refrigerator vibration comes from the compressor, the pump that moves refrigerant through the cooling coils. A fixed-speed compressor runs at about 3,000 to 3,600 RPM, which is 50 to 60 Hz. That’s faster than your phone can measure (about 30 Hz). So the frequency on this page may be wrong, or the tool may say the main vibration may be faster than your phone can measure. The strength reading still works, and that’s what this test is for.
Inverter fridges change compressor speed to match the cooling needed. At low speed, the compressor may sit inside your phone’s range, so the frequency you see can change from one test to the next. That’s normal.
The most useful comparison is on and off. Test once with the compressor running and once when it’s quiet. If the shake is the same both times, look for another source, like a nearby washer or a floor that moves when people walk.
Normal sounds and problem sounds
Normal: a steady hum, a click when the compressor starts or stops, gurgling or hissing as refrigerant flows, cracking as parts warm and cool, and the ice maker filling and dropping ice.
Worth a closer look: a rattle that comes and goes with the compressor, a buzz from behind the toe grille at the bottom front, grinding or squealing from a fan, and loud knocking when the compressor starts or stops.
Common causes and fixes
Unplug the fridge before you pull it out or reach behind it.
Not level, or resting on its rollers
Many fridges roll on wheels but should stand on front leveling legs. If the legs are up, the fridge rocks and passes every hum into the floor. Lower the legs until they press firmly on the floor, then check it’s level side to side.
Touching the wall or cabinets
A fridge pressed against a wall, cabinet or another appliance turns the whole thing into a sounding board. Leave the gap your manual asks for.
Things rattling on top or behind
Bottles, bowls or a box on top can buzz. Behind the fridge, the water line to the ice maker can tap the wall. Clear the top and fix the tube so it can’t touch the wall.
A loose drain pan or grille
On many models, a drain pan sits under the fridge behind the toe grille. If it’s out of place, it buzzes against the frame. Reseat it and the grille.
Dirty coils or a noisy fan
Dusty condenser coils make the compressor run longer. A fan that hits debris or has worn bearings rattles or squeals. Clean the coils the way your manual shows.
When to call a repair person
Call if the fridge knocks or bangs when the compressor starts, grinds, or stops cooling. Also call if the compressor clicks on and off every few minutes while the fridge stays warm.
What this tool can’t measure
- The compressor’s true speed. It’s usually above your phone’s limit.
- Noise. Much of a fridge’s sound is fan noise and refrigerant flow. A fridge can sound loud with very little vibration, so a low reading doesn’t mean it’s quiet.
- Cooling problems. It can’t check refrigerant, temperature or electrical parts.
- A certified result. The labels come from a general machine scale (ISO 10816-1) used as a rough guide. The result is a good guide, not a certified measurement.
Frequently asked questions
Why is my fridge vibrating?
Most fridge vibration comes from the compressor, which runs on and off all day. It gets worse when the fridge isn't level, rests on its rollers instead of its legs, or touches a wall or cabinet. Loose items on top and a loose drain pan underneath can turn a small hum into a rattle.
Is it normal for a refrigerator to hum and vibrate?
Yes. A running compressor always makes a hum and a light buzz you can feel. Clicks when it starts and stops, gurgling, and the ice maker dropping ice are normal sounds too. Loud knocking, grinding or constant rattling are not.
Why does the test say the vibration may be faster than my phone can measure?
A fixed-speed fridge compressor runs at about 3,000 to 3,600 RPM, or 50 to 60 Hz. Your phone can only measure up to about 30 Hz, so the true frequency can show up as a false, lower number. The strength reading still works, so use that.
Why does my fridge shudder when the compressor turns off?
The compressor sits on rubber mounts and rocks for a moment as it stops. A short shudder is often normal. If it's a loud bang, it's getting worse, or the fridge also moves, have it checked.
Should a refrigerator be level?
Side to side, yes. Many manuals ask for the front to sit slightly higher than the back so the doors swing shut on their own. Check your manual for the exact setting for your model.
Last updated .