Diagnosing a built-in by the noise it makes

Where the sound is made, and the ten-second test that tells you

Work in this order and you will usually have the answer before a technician arrives. First the door test above: open it, listen, and note whether the sound stops, changes or ignores you. Second, the touch test. Rest a hand flat on the cabinet side, then on the floor at the base of the unit, then on the countertop or the cabinetry above. Vibration you can feel in the floor and in the surrounding joinery but not in the cabinet skin is being transmitted rather than generated, which points at mounts, a loose panel or a resonating surround instead of a failing part. Third, the cycle test. Stand there with a watch and find out whether the sound tracks the running cycle: present the whole time the compressor runs and absent when it stops, or completely independent of it. A noise independent of the cycle is nearly always the ice maker, the water valve or something outside the appliance. Record thirty seconds of it on a phone while you are there, close to the source and then a step back. A recording is worth more on the phone call than any adjective.

• Door open: stops or changes means inside a compartment, unchanged means the grille or outside
• Hand on the floor and the cabinetry: felt but not heard at the cabinet means it is being transmitted
• Timed against the cycle: independent of the compressor points at water or ice, not refrigeration
• Note whether it appeared overnight or grew over weeks — sudden is debris, gradual is a bearing
• Note the season, since several of these faults only speak up when the room is hot

The sounds that mean the machine is working correctly

A built-in is not a silent appliance, and a good half of the noise calls in this trade are healthy machines being heard properly for the first time — usually after a remodel opened the kitchen up, or after the house went quiet at night. A soft trickling or gurgling a minute or two after the compressor stops is refrigerant equalizing through the system and is entirely normal. A brief sizzle, tick or pop from behind the rear panel every several hours is the defrost heater meeting frost and melt water, which is the circuit doing precisely what it exists to do. A clunk followed by cubes falling is the ice maker harvesting. A buzz of a few seconds from low down at the back, usually right after that clunk, is the water valve opening to refill the mold. A rising whir when the compressor starts is the condenser fan spinning up. Some newer compressors vary their speed with the load instead of switching on and off, so their pitch rises and falls slowly through the day, and owners moving from an older unit consistently report that as a fault.

• Trickle or gurgle after shutdown — refrigerant settling
• Sizzle, pop or tick every few hours from the back panel — defrost
• Clunk, then cubes dropping — ice harvest
• Short buzz low at the back — the water inlet valve filling the mold
• A slow rise and fall in pitch over minutes — a variable speed compressor tracking the load

The sounds that name a part

Now the useful half. A rattle or a rapid tick from the grille that is present exactly when the unit runs is almost always the condenser fan: something on the blade, something loose in the cavity, or the blade itself out of balance. Debris arrives from the room, so this is the fault that turns up suddenly on a machine that has been quiet for a decade, and on a property with a workshop, a garage or open ground nearby the cavity collects more than dust. A sing, hum or whine at the grille that has grown a little louder each week is different — that is a bearing, in either the condenser fan or the compressor, and bearings do not recover. Fast, light ticking or a chirp from inside a compartment that stops when the door opens is the evaporator fan blade brushing ice, which means you have a defrost problem announcing itself through the speaker before it announces itself through the food. A deep hum or drone you feel more than hear, transmitted into the cabinetry and the floor, is generally compressor mounts that have gone hard with age. A buzz that only appears at certain points in the cycle is often the drain tray sitting against the compressor housing rather than in its clips.

• Rattle or tick, only while running, from the grille: debris on the condenser fan or in the cavity
• Whine or sing that grows week by week: a bearing, in a fan motor or the compressor
• Fast ticking inside the box, stops with the door open: the evaporator fan touching ice
• Deep drone through the floor and joinery: compressor mounts
• Intermittent buzz at the grille: a loose drain tray, a loose grille panel or a fastener backed out
• Scraping or grinding, anywhere: something is making metal-to-metal contact and it should not run like that

Click, hum, click: the one that should not wait a week

There is one sound pattern on this equipment worth interrupting your day for. A click, then a low hum for one or two seconds, then another click and silence, repeating every few minutes, is a compressor attempting to start and being shut down by its overload protector before it gets going. It may be the start components, it may be the compressor itself, and occasionally it is a supply voltage problem, but what it is not is something to live with, because each of those attempts is a hard electrical and mechanical event and the cabinet is not cooling in between them. The second item on the short list is any scraping or grinding from a fan. A blade making contact is minutes to hours from stopping, and once a condenser fan stops the system loses its ability to reject heat entirely: head pressure climbs, the compressor carries a load it was never designed for on the hottest afternoon of the year, and a modest part turns into an expensive one. The third is a squeal on startup that has begun to last longer each time. These three are the exceptions to the general rule that a noisy refrigerator is not an emergency.

• Click, hum, click every few minutes with no cooling: stop using it and get it looked at
• Scrape or grind from a fan: switch it off at the breaker if you cannot get service quickly
• A startup squeal getting longer week by week
• Any noise arriving alongside a burning or hot electrical smell, which is not a noise problem at all

The noise that turns out to be plumbing, cabinetry or a bottle

A fair share of noise complaints are solved without opening anything. A bang or thud in the wall a second after the ice maker stops filling is water hammer in the supply line, produced by the valve closing quickly against a long run of pipe with no cushion, and the fix is plumbing rather than refrigeration. A vibrating buzz that appears at one particular point of the cycle and vanishes if you touch the cabinetry is resonance: a built-in is anchored into a surround, and the panel, the toe-kick or a loose grille screw is amplifying a vibration the appliance itself makes quietly. Bottles ringing against each other on a shelf, a sheet pan leaning on a cabinet wall, or a bin of ice settling as cubes fuse together will all produce sounds owners describe as coming from inside the machine, which they do, without any part being involved. On any unit standing on an uneven floor, the cabinet can rock a fraction on one foot and tap in time with the vibration from the compressor, and leveling it stops the noise dead. Rule these out first, because they cost nothing and they account for a surprising number of visits.

• Bang in the wall after the ice maker fills: water hammer
• Buzz that changes when you press the grille, the toe-kick or the cabinet above
• Ringing, chinking or shifting from the food compartment or the ice bin
• A cabinet rocking on one foot against an uneven floor
• A second refrigerator or a freezer elsewhere in the house, being blamed on the one you are standing next to

How to describe it so the right part travels to you

The difference between one visit and two is often the sixty seconds spent describing the sound accurately, because it decides what a technician loads before leaving. Four details do most of the work. Where it comes from — the grille at floor level, high on the cabinet, or inside a compartment. Whether it runs steadily or comes and goes with the cycle. Whether it changes when the door is open. And whether it arrived in one day or built up over months. Add the season and the room if the unit is not in the kitchen, because ambient temperature changes both what fails and how loudly. Then play the recording. Nobody can name a part from the word rattle, since a fan blade with a bread tag on it, a drain tray out of its clips and a grille screw backed out are three completely different jobs and every one of them gets described with the same word. Those details, with the recording, are usually enough to separate debris on a blade from a worn bearing, and either of those from a loose drain tray or a resonating panel, before a single fastener has been touched.

• Where: grille, high on the cabinet, or inside the box
• When: constant, cycling with the compressor, or independent of it
• Door test result, in one word
• Sudden or gradual, and how long it has been going on
• A thirty-second recording, close in and then a step back