Appliance repair glossary

A replacement part made by someone other than your appliance's manufacturer, sold to fit your model.

Aftermarket covers an enormous quality range, from a second production line at the factory that built the original to the cheapest possible copy. The signal to look for is a published part-number cross-reference and a stated warranty. The warning sign is a marketplace listing whose only claim is that it is compatible with a list of brands. In the United States the Magnuson-Moss Warranty Act stops a manufacturer conditioning your warranty on branded parts unless it supplies them free, so fitting aftermarket does not void a warranty by itself.

The tall finned spindle in the middle of a top-load washer tub that twists back and forth to drag clothes through the water.

An agitator moves the laundry rather than the water. Inside the top of most agitators sit small plastic drive dogs; when they wear, the top half spins freely while the bottom half still oscillates, and clothes come out barely washed even though the machine sounds completely normal. Grab the agitator and try to turn it by hand against its direction of travel — if it moves freely, the dogs have gone.

A metal bracket that screws to the floor or wall and hooks a freestanding range's rear leg so the appliance cannot tip forward.

Freestanding ranges are designed to be secured this way and normally ship with the bracket in the box, but fitting it is an installation step that is easy to skip — so the first thing to do is check whether yours actually has one. Without it, weight on an open oven door, such as a child climbing on it, can tip the whole range over. Slide the range forward and look for a bracket engaging the rear leg. If there is not one, the manufacturer will sell you the part and it takes about fifteen minutes to fit.

Safety. A range without an anti-tip bracket can tip forward under the weight of a child on an open door. Fit one before you use the oven again.

The heating coils in an electric oven — one across the cavity floor doing most of the baking, one in the roof for browning.

A failed element usually announces itself visually: a blister, a break, or a bright scorched section along the coil. With the oven cold and the breaker off, it unscrews from two mounting screws at the back of the cavity and pulls forward on its two terminals. This is the most common electric-oven repair and one of the few where the visual check is as reliable as a meter reading. The broil element fails and is replaced the same way, but it is easier to overlook because most cooking never calls for it — on ovens that cycle the broiler during normal baking, a dead one reads as food browning unevenly rather than as an oven that will not heat.

The caged fan that moves air through a dryer or a range hood — not the motor, the wheel the motor turns.

In a dryer the blower wheel pulls heated air through the drum and pushes it out the vent, so a cracked hub or a lint-packed wheel shows up as weak airflow at the outside hood and long drying times. The plastic hub cracks and slips on the motor shaft, which is why the motor can sound perfectly healthy while the wheel barely turns. In a range hood, caked grease unbalances the wheel and makes the whole hood buzz.

A return visit to fix something that was not fixed the first time, or that failed again inside the warranty period.

The trade word for a repair that did not hold. A callback inside the labour warranty should carry no charge at all — no trip charge, no diagnostic, no labour. Ask how callbacks are handled before you book, and get the answer on the estimate. A company that charges a fresh trip charge to come back and finish its own job is telling you what its warranty is actually worth.

A component that stores electrical charge — used to give motors a starting kick and, in a microwave, to build the thousands of volts a magnetron needs.

Motor start capacitors turn up on compressors and some large motors and are relatively benign. The high-voltage capacitor in a microwave is a different object entirely: it stores enough energy to stop a heart and it holds that charge after the oven is unplugged, sometimes for days. It must be discharged through a resistor before anyone touches the chassis. If you do not have a discharge tool and know the procedure, this repair is not yours.

Safety. A microwave high-voltage capacitor holds a lethal charge with the oven unplugged. Unplugging does not make it safe. Discharge it through a resistor, or do not open the cabinet.

The sealed pump at the bottom of a refrigerator, freezer or wine cooler that circulates refrigerant and does the actual cooling.

The compressor is the most expensive single component in a refrigeration appliance and the one most often blamed for faults it did not cause. A compressor that clicks on and off every few minutes is usually a failed start relay — a part costing a small fraction of the compressor — and cleaning the condenser resolves a large share of no-cooling calls outright. Replacing a compressor means opening the sealed system, which is EPA Section 608 work.

The black grille at the back or underneath a refrigerator or freezer that dumps the heat pulled out of the cabinet into your kitchen.

A refrigerator does not make cold; it moves heat, and the condenser is where that heat leaves. Blanket the coil in dust and pet hair and the appliance cannot reject heat fast enough to satisfy its thermostat, so it runs continuously, gets hot at the back, and eventually stops holding temperature. Vacuuming it with a brush attachment is free, takes fifteen minutes, and is the single highest-value piece of appliance maintenance in the house.

The circuit board that runs the appliance — reads the sensors, times the cycle, and switches the motors and heaters.

Boards are expensive, rarely returnable once installed, and blamed far more often than they fail. The honest order of diagnosis is sensors and switches first, board last: a thermistor reading out of range makes a perfectly good board behave like a broken one. Before you authorise a board, ask what was tested to rule out the cheaper causes, and confirm the board is still available for your model number.

A low-wattage element under the evaporator coil of a frost-free refrigerator or freezer that melts accumulated frost several times a day.

Frost-free does not mean frost never forms; it means frost is melted off on a schedule and drained away. When the heater fails, ice packs into the evaporator fins until air can no longer pass through them, the cabinet warms, and the appliance runs constantly against a block of ice. Reaching the heater usually means a full manual defrost first, which is most of the labour on this job.

A small bimetal disc clipped to the evaporator coil that closes when the coil is cold, allowing the defrost heater to run.

It is the safety interlock of the defrost circuit — it stops the heater running when the coil is already warm. Because it must be closed when cold, it has to be tested straight out of the freezer before it warms up on the bench; test it warm and a perfectly good part reads open. Symptoms are identical to a failed defrost heater, which is why both are tested together.

The clock that decides when a frost-free refrigerator or freezer stops cooling and runs its defrost cycle instead.

Older machines use a mechanical timer you can advance with a screwdriver until it clicks into defrost — if the heater then comes on, the timer was the fault and the rest of the circuit is fine. Newer machines replace it with adaptive defrost control on the main board, which decides defrost intervals from run time and door openings rather than on a fixed clock. Same symptom either way: gradual, relentless icing.

What a company charges to come out, find the fault and tell you what the repair will cost — separate from the repair itself.

It buys diagnosis, not a fix. The question that matters is whether it is credited against the repair if you go ahead: many companies waive or credit it in full, some credit half, and some do not credit it at all. Ask before you book, and get the answer written on the estimate. If you decline the repair, the fee is still owed — that is what it is for.

The large flexible rubber gasket that bridges the door opening and the drum on a front-load washer.

It is not the same object as a refrigerator door gasket — it flexes with every spin and it holds standing water in its lower fold, which is why it is the number one home of front-loader mould. Fold it all the way back and look for splits at the bottom, where the tub flexes hardest. Buy OEM here: a near-fit boot leaks forever and no amount of fitting effort corrects it.

The magnetic rubber seal around a refrigerator, freezer, dishwasher or oven door that keeps conditioned air in and room air out.

Test it with a dollar bill: close the door on it and pull. If it slides out with no drag anywhere around the perimeter, that section is not sealing and the appliance is fighting a continuous leak of warm humid air. Clean the gasket with warm soapy water before condemning it — sticky residue stops a perfectly good seal closing, and that fixes a surprising share of these.

The set of switches in a microwave door latch that must all agree the door is shut before the magnetron can run.

Microwaves use two or three interlocks in series plus a monitor switch whose only job is to short the supply and blow the line fuse if the others fail out of sequence. That design is what keeps microwave energy inside the box. It is also the most common microwave failure, and it presents as a dead oven or a tripped breaker when the door opens. Do not defeat an interlock under any circumstances.

Safety. Discharge the high-voltage capacitor before your hands go near a microwave chassis. It holds a lethal charge with the oven unplugged.

The small electric pump that empties a washer or dishwasher at the end of a cycle.

A machine that hums but will not drain usually has a jammed pump rather than a dead one — coins, hair clips and bra wires are the classics. Most front-load washers have an access panel at the bottom front with a filter and a short drain hose behind it; clearing it is free and resolves the most common no-drain call outright. On dishwashers, check the air gap and the disposal knockout plug first, because a newly fitted disposal with the plug still in blocks the drain completely.

The rubber belt that transmits motor power to a dryer drum or a washer transmission.

The signature is unmistakable: the motor runs, nothing turns, and the drum spins freely by hand with no resistance at all. On a dryer the belt wraps the entire drum and the failure is usually visible the moment the panel is off. Replace the idler pulley at the same time if the old belt shredded — a seizing pulley is what ate it, and a new belt on a bad pulley fails again within months.

The duct that carries hot, moisture-laden, lint-laden air from the back of the dryer to the outside of the building.

This is the most consequential piece of maintenance in the house. Lint accumulating in the duct restricts airflow, which makes the dryer run hotter and longer, which bakes more lint onto the duct walls. The US Fire Administration counts roughly 2,900 clothes dryer fires a year in residential buildings, and failure to clean is the single leading cause of them. Clean the full run and the exterior hood annually, and replace flexible foil duct with rigid or semi-rigid metal — ribbed foil traps lint by design.

Safety. Lint is highly combustible and a blocked dryer vent is a genuine fire risk, not a performance complaint. If your dryer takes two cycles to dry a load, treat the vent as the first thing to check, not the last.

The federal certification a technician must hold to open, recover from, or recharge a sealed refrigerant system.

Required under the US Clean Air Act. Anyone servicing refrigerant in a refrigerator, freezer, wine cooler or ice machine must be 608-certified, and it is illegal to knowingly vent refrigerant to atmosphere. Type I covers small appliances, which is the category almost all household refrigeration falls into. If a quote involves a leak, a recharge, or a compressor, ask for the certification — a technician who holds it will not mind being asked.

A letter-and-number string the appliance displays to name the circuit it is unhappy with.

A code points at a circuit, not at a part. An F21 on a washer means the machine did not drain within its expected time — it does not mean the pump is dead, because a blocked filter produces the identical code. Write the code down exactly, including any leading letter, and give it to the technician when you book. It genuinely changes which parts get loaded on the van, and codes are model-specific, so the code plus the model number is the useful pair.

The coil inside the freezer compartment where refrigerant boils and absorbs heat — the part that actually makes things cold.

It sits behind the rear panel of the freezer, and on most modern refrigerators one evaporator cools both compartments, which is why a fridge that is warm while the freezer is still cold is almost always an airflow fault rather than a cooling fault. A light even dusting of frost on the coil is normal; a solid slab means the defrost circuit has quit. Never chip ice off an evaporator — puncturing a tube destroys the sealed system outright.

The two bases a repair can be priced on: one quoted price for a named job, or an hourly labour rate plus parts.

Flat rate covers parts and labour for the named repair regardless of how long it takes — easier to compare between companies, and it protects you if the job runs long. Time and materials bills the technician's hours plus parts, and can be cheaper on a genuinely quick fix. Neither is dishonest, but the same repair looks wildly different on two estimates written on different bases. If you are quoted hourly, ask three things: the rate, the minimum billable increment, and whether travel time sits inside or outside it. A rate quoted per hour but billed in one-hour blocks is a very different number on a twenty-minute repair.

A small float in the floor of a dishwasher tub that tells the control when enough water is in and stops the fill.

It is an overfill safety, so a stuck float reads as a full tub and the machine refuses to fill at all — water is available at the tap, and nothing happens. Lift the float cup by hand and let it drop. If it sticks, or grinds, clean under it before ordering anything: food debris and detergent scale under the cup account for most of these.

The metal mesh or baffle panel under a range hood or over-the-range microwave that catches airborne cooking grease.

Hold one up to a light. If light does not pass through it, it is no longer a filter — it is a restriction, and the blower is working against it. Aluminium mesh and stainless baffles both go in the dishwasher, and a monthly wash is the whole maintenance routine. A grease-loaded filter directly above a gas burner is also a fire risk, which is the reason this is monthly rather than annual.

Safety. A grease-saturated filter sits directly in the path of a burner flare-up. Wash it monthly — this is a fire-prevention task, not a cleanliness one.

The resistive coil that produces heat in an electric dryer, a dishwasher, or an oven.

In a dryer it is the usual second suspect after the thermal fuse on a machine that tumbles without heat, and it tests in seconds for continuity. In a dishwasher it heats the wash water and drives the heated-dry cycle — but check first whether your machine uses condensation drying and has no element at all, because a lot of European-designed dishwashers do not. Gas appliances have no heating element; they have an igniter and a burner.

The glow bar in a gas oven or gas dryer that heats until it draws enough current to open the gas safety valve and light the burner.

It does two jobs at once, which is why a weak igniter is such a confusing fault: it has to glow hot enough to ignite gas and draw enough current to hold the valve open. An igniter that glows brightly but never lights the burner has failed at the second job and still needs replacing. If it glows and then dies without the burner lighting, the fault is the valve coils instead. Anything beyond swapping the igniter itself is licensed gas work.

Safety. If you smell gas at any point, stop, leave, and call the gas utility from outside. Gas piping and valve work is licensed trade work in every state.

The low, finned disc in the base of an agitator-free top-load washer that rotates the whole load rather than beating through it.

The practical difference for you is capacity and wear: an impeller machine takes bulkier loads and is gentler on fabric, an agitator machine is usually faster and more aggressive on heavy soil. Impeller machines are also the ones that most commonly get accused of not filling with enough water — they are designed to wash in less. The word also describes the small vaned wheel inside a drain pump.

The knob-operated switch behind an electric cooktop burner that sets heat level by cycling the element on and off.

Electric burners have no intermediate power setting; they are full on or full off, and the infinite switch simply varies the ratio. That is why a failed one gives you a burner that is either blazing or dead with nothing in between — the contacts have welded closed. Test the element for a short first, because it fails the same way and is often the cheaper of the two.

The electrically operated valve where the household water supply enters a washer, dishwasher, refrigerator or ice maker.

It is a solenoid valve: energise the coil and the valve opens. Slow fills and no-fill faults usually trace to a silted inlet screen rather than a dead coil, so pull the screens before ordering anything. The failure mode that matters is a valve that will not close — that is a flood risk, so shut the taps until it is replaced, and never leave a washer with a suspect inlet valve connected and unattended.

The company's guarantee on its own work — how long it will come back and refit or redo the repair at no charge.

This is the promise that tells you what a company thinks of its own diagnosis, and its length varies widely — independents and factory-authorised agents work to different norms, and there is no industry standard to hold anyone to. So do not ask whether they warranty their work; ask exactly what is covered and for how long, and get the answer in writing. The precise question: if this same fault returns inside the period, is the return visit free of trip charge, diagnostic and labour? Anything less than all three is a partial warranty and deserves to be described as one.

Two separate things: a licence is state or local permission to do the work, insurance is who pays if something goes wrong in your home.

Appliance repair licensing varies by state — some require a contractor licence, some regulate only the gas and electrical portions of the work, and some do not license the trade at all. Insurance is not optional in the same way but is entirely the company's choice to carry. Ask for the licence number and for a certificate of general liability insurance naming the company. Both are verifiable, and a legitimate company produces them without friction.

A safety switch under the lid of a top-load washer that prevents the drum spinning while the lid is open.

A washer that fills and washes but refuses to spin or drain, with no error code and no noise, is a lid switch until proven otherwise. Listen for the click as you press the lid closed. Because it is a two-screw part on most machines and one of the cheapest components in the appliance, it is worth checking before anything with a motor in it.

The vacuum tube that generates the microwave energy that heats your food.

A microwave that runs perfectly — light on, turntable turning, fan running — and heats nothing is the classic magnetron symptom. It is also the classic symptom of a failed high-voltage diode or capacitor, both of which are cheaper and fail more often, so those get ruled out first. On a countertop unit the magnetron usually costs a meaningful share of a new microwave, which is why the honest answer is often replacement.

Safety. Genuine electrocution risk. The high-voltage capacitor must be discharged first, and it holds a lethal charge with the oven unplugged.

The code on the appliance's data plate that identifies exactly which machine you own — not the name printed on the front.

Every parts supplier searches on the model number, and the series name on the front of the appliance returns nothing. The plate hides on a surface you can only see with the door open: the door rim, the tub edge, behind the kick plate, or up inside a range hood behind the filters. Photograph the whole plate, not just the model number — the serial beneath it tells a parts desk which production run you have, which matters whenever a part changed mid-model.

Two metal strips inside a dryer drum that measure conductivity across tumbling clothes to decide when the load is dry.

When auto-dry cycles end after ten minutes with the load still wet, the sensor is reading dry because it is insulated rather than because the clothes are. Fabric softener and dryer-sheet residue builds an invisible film across the bars. Wipe them with rubbing alcohol first — that fixes it for free far more often than the part does.

The handheld meter that reads voltage, resistance and continuity — and continuity, meaning whether current can travel through a part at all, is the single most useful test in appliance repair.

Set to continuity, the meter beeps when a complete path exists. A thermal fuse, a heating element, a door switch or a thermostat either passes current or it does not, and that one reading is the difference between replacing the part that failed and replacing three hoping one of them was it. Set to ohms, the same meter checks a thermistor or an oven sensor against the resistance chart on the tech sheet instead of replacing it on a hunch. Always unplug the appliance first, and isolate the component from its circuit or you will be measuring the rest of the machine rather than the part.

The part the appliance manufacturer specifies, in manufacturer packaging, usually built by the same supplier that made the original.

What the premium buys is a guaranteed dimensional and firmware match, a manufacturer warranty, and a part number you can verify against the exploded diagram for your exact model. That matters enormously for control boards, door seals, safety interlocks and sealed-system components, and hardly at all for belts, rollers, thermostats and fuses. Note that the phrase genuine replacement on a marketplace listing is marketing language, not a specification.

The guarantee on the replacement component itself, separate from — and usually a different length to — the warranty on the labour to fit it.

Almost every repair carries two warranties running at once, and confusing them is where disputes start. The part warranty normally comes from the part manufacturer and is passed through by the repair company. If the part fails inside it, the part is free — but whether the labour to refit it is also free depends entirely on the labour warranty, which is a different promise from a different party. Ask for both periods in days or months and get them on the invoice; the word warranted on its own means nothing.

The working fluid that carries heat out of a refrigerator, freezer, wine cooler or ice machine.

It circulates in a closed loop, so a correctly built system never consumes it — if a machine is low on refrigerant, it has a leak, and topping it up without finding the leak simply sells you the same repair again next year. Many current appliances use R-600a isobutane, which is flammable and changes how the machine must be handled. Handling refrigerant requires EPA Section 608 certification, and venting it to atmosphere is illegal.

Safety. R-600a isobutane is flammable. Sealed-system work is licensed, EPA-certified work in every state — there is no homeowner version of this repair.

The closed refrigerant loop — compressor, condenser, capillary or expansion device, and evaporator — brazed shut at the factory.

Everything else on a refrigerator is a component you can unplug and swap. The sealed system is not: opening it requires recovery equipment, brazing, evacuation and a measured recharge, and it is the dividing line between a repair anyone competent can do and one that needs a licensed, EPA-certified technician. It is also the point at which the economics change, because sealed-system work on an older cabinet routinely approaches the price of replacing it.

The dampers that stop a washer's inner tub swinging freely inside the outer cabinet during a spin.

Test them with the machine empty: push the drum down and let go. Three or more bounces means the dampers have given up and the tub is now free to hammer the cabinet on every spin, which is what destroys bearings next. Replace them as a full set — one new damper against three tired ones simply relocates the imbalance. Check first that the shipping bolts were removed at installation, because that produces identical symptoms for free.

An electromagnet that pulls a plunger to open or close a valve or throw a mechanical latch when the control energises it.

Solenoids are everywhere in appliances: water inlet valves, gas valve coils, dispenser actuators, door locks. A solenoid either has a working coil or it does not, and the coil measures a specific resistance, which makes them among the most satisfying parts to diagnose. Gas valve coils are the classic intermittent no-heat on a gas dryer — they work cold and drop out once warm, and they are sold and replaced in pairs.

A part not carried on the van or in local stock, ordered against your specific model and usually non-returnable once it ships.

This is the one situation where a deposit before work is completed is normal and reasonable: the company is buying a part it cannot resell if you change your mind. A deposit covering the cost of the part is standard practice. A deposit covering the whole repair, labour included, is not. Get the part number, the price and the expected arrival date written down, and pay the balance on completion.

The rotating perforated arm in a dishwasher that fires water at the racks, driven by the force of the water itself.

Nothing motorises a spray arm; it spins on reaction, so anything that blocks a jet or fouls its rotation degrades the wash immediately. The tell is asymmetric: the bottom rack comes out clean and the top rack does not, or vice versa. Twist the arms off, clear each jet with a toothpick, and check that a tall item in the rack is not stopping the arm turning. This is the most common cause of poor cleaning and it is free to fix.

The small plug-on device at the side of a refrigerator compressor that switches in the start winding for the moment the compressor kicks over.

It is the cheapest part on the machine and the one most often mistaken for a dead compressor. The symptom is a compressor that clicks on and off every few minutes while the cabinet slowly warms. The test takes five seconds: unplug the appliance, pull the relay off the compressor, and shake it. A rattle means it has failed internally. Replacing it costs a fraction of the compressor diagnosis it prevents.

The folded diagram taped inside the appliance — wiring, component resistance values, service-mode entry and the fault-code table.

It is the manufacturer's own diagnostic key, and it lives behind the kick plate, inside the control housing, or under the top panel of the machine it belongs to. It is what turns a thermistor reading into a verdict, because the resistance chart on it is the only reference that says what that reading should be at that temperature. Put it back where you found it — the next technician will need it, and a missing tech sheet adds real time to a diagnosis.

A one-shot safety fuse that permanently opens if the appliance exceeds a set temperature, and never resets.

It is the most common reason a dryer tumbles without heat, and it is a symptom rather than a cause. A thermal fuse blows because the appliance overheated, and on a dryer that overheating is almost always a restricted vent. Fitting a new fuse without clearing the vent gets you a new fuse and the same fault. Never bypass one — it is the last line of defence between a blocked vent and a fire.

Safety. Never jump out or bypass a thermal fuse. It is a fire-safety device, and it blew because something upstream was overheating.

A small bead sensor whose electrical resistance changes with temperature, telling the control board how cold or hot the appliance actually is.

It is how a modern appliance knows anything about temperature, and a drifted thermistor makes a perfectly good control board behave like a broken one — the cabinet runs constantly, or the oven bakes ten degrees off, because the board is acting correctly on a wrong number. Unplug the appliance, unclip the sensor and measure its resistance, then compare it against the chart on the tech sheet. Check the sensor before anyone sells you a board.

A fee for travelling to your address, charged whether or not any work is done and separate from diagnosis.

Some companies fold it into the diagnostic fee, some bill it as its own line, and some waive it inside a radius and charge it outside. None of that is dishonest — quoting one estimate that includes it against another that does not is what causes the trouble. Ask whether the quoted figure includes travel, whether it is credited against the repair, and whether a return visit for the same fault carries it again.

The sealed bearing that carries the washer drum shaft where it passes through the back of the outer tub.

The sound is unmistakable: a rising roar on spin, like a jet engine spooling up, that grows louder over months. The part itself is cheap. The labour is not — the machine comes apart almost completely to reach it, and on many front-loaders the outer tub is sealed and has to be replaced as a unit. This is the repair where the honest advice is to price a new machine before committing.

The replaceable cartridge inside a refrigerator or ice maker that filters the water going to the dispenser and the ice mould.

A consumable, not a repair part, rated for roughly six months or a few hundred gallons. A clogged filter chokes flow to a trickle and produces small hollow cubes and slow dispensing, which is exactly what a failing inlet valve looks like — so if nobody remembers changing it, change it before diagnosing anything else. Aftermarket cartridges that are dimensionally close but not exact are a common cause of a leak that starts the week a filter was swapped.

A tiny actuator that expands a wax pellet with heat to push a latch open — most commonly the dishwasher detergent dispenser door.

There is no motor in it at all. Current heats a sealed wax charge, the wax expands, and a pin pushes the latch. When it fails, the dispenser door simply stays shut through the whole cycle and the dishes come out with an undissolved block of detergent in the cup. Most brands sell it only as part of a complete dispenser assembly rather than on its own.

An itemised document, given before work starts, separating parts, labour, trip charge and tax, with the warranty terms on it.

It is the single most protective thing you can insist on, and it costs nothing. A usable estimate names the part being fitted, prices parts and labour separately, states the trip charge and whether the diagnostic is credited, gives the parts and labour warranty periods in days or months, and sets a figure above which the company must call you before proceeding. A verbal figure is not an estimate and gives you nothing to hold anyone to.