Whirlpool Refrigerator Repair in Toronto — Running constantly / never shuts off

• The most common runs-constantly root on Whirlpool-built fridges (also Maytag, Amana, Inglis, KitchenAid badges) is a frosted-over rear evaporator from a dead defrost circuit: an open defrost heater WP12729128 (115V 135W; replaces 12729128 / AP6005557 / PS11738607) or a bimetal defrost thermostat WPW10225581 (replaces W10260437 / 2319914 / 2321799) stuck open lets frost sheet the coil edge-to-edge, so airflow chokes and the compressor never satisfies the thermostat. The field tell is a frost-packed rear freezer panel with the box running 24/7. We pull the evaporator cover and ohm the heater and bimetal for continuity before condemning either, because a $20-$45 thermostat is routinely misread as a board fault on a non-stop box.
• On adaptive-defrost (Jazz-board) bottom-mount and French-door cabinets, the runs-constantly fault is the control board itself, not the heater: the OEM adaptive-defrost control W10503278 (current OEM WPW10503278, AP6022400) is the defrost timer, and a known failure mode is the compressor relay sticking ON so the unit runs continually and never enters defrost, which then ices the coil. We run Forced Defrost in service diagnostic mode and confirm the board actually drops the compressor and energizes the heater before choosing between a low-cost WP12729128 heater / WPW10225581 bimetal and the pricier WPW10503278 board - and the board must be reprogrammed from the serial-plate code after replacement or it won't run defrost.
• A dirty or blocked condenser is the classic mechanical runs-constantly driver: when the condenser coils are caked with dust and pet hair the refrigerator can't reject heat, so it runs nonstop trying to pull temperature down. Paired with that is a failed condenser fan motor W10124096 (kit includes blade, harness and screws; crosses to 2188538 / 2315558 / W10124096VP / AP4318657 / PS1957416, shared across Amana, Inglis, KitchenAid, Maytag, Roper) - the motor that draws air over the condenser. We clean the coils and spin-test the condenser fan for a dry bearing or an obstructed blade before parts, because a $40 fan or a brush-out fixes a non-stop compressor that gets misdiagnosed as a sealed-system loss.
• A stalled evaporator fan motor W10189703 (current OEM WPW10189703; crosses W10208121 / 2219647) makes the box run constantly with the fresh-food side warm: this line-voltage fan pushes cold air off the freezer evaporator into the fridge, so when it seizes the fridge never reaches setpoint and the compressor never cycles off even though the freezer holds. The signature is a fan chirp/squeal behind the freezer rear panel that quiets when the door opens. We spin the blade by hand and ring out the windings for continuity, and on iced units we FIX the defrost circuit (heater WP12729128 / bimetal WPW10225581) first, because a fan dropped onto a still-frosting coil re-ices and the box keeps running.
• A door gasket that no longer seals is a real runs-constantly driver, not user error: a torn or compressed gasket lets warm humid GTA air leak in, so the evaporator coils ice over faster than the defrost cycle can clear them and the compressor runs to keep up. We run the dollar-bill pull test around the perimeter and check door alignment/level, then reseat or replace the model-specific gasket before parts-cannoning the defrost circuit - replacing a heater on a box with an air leak is a guaranteed repeat non-stop call.
• On single-evaporator cabinets with a clean, frost-free coil, a damper/diffuser stuck OPEN makes the fridge over-cool and run constantly: the motorized air baffle W10899382 (incorporates/replaces air diffuser W10128734) meters freezer air into the fresh-food section, and jammed open it dumps too much cold so the box never satisfies. A drifting refrigerator/freezer thermistor WPW10384183 (AP6020677 / PS11753996; replaces W10384183 / 2118228) does the same by feeding the board bad temperatures so it short-runs the compressor. Whirlpool's Service Test 03 cycles the baffle (13 = open, 23 = closed) and the sensor test reports the thermistor (01 good / 02 open / 03 shorted); we drive the damper and ohm the thermistor against spec before ordering either.
• A 'PO' power-outage flag on the display after a blackout is informational only and is NOT a runs-constantly fault - it just signals the freezer warmed past ~18F while power was out. But a box genuinely running nonstop after a power event is usually catching up on a warmed cabinet and should settle within hours. We confirm cabinet temperatures and clear the PO flag first, then only diagnose the defrost circuit, condenser/fan, gasket or damper if the compressor is still running 24/7 after the box has had time to recover, so a normal recovery isn't misdiagnosed as a part failure.

Whirlpool running constantly / never shuts off in Toronto — the local specifics

• The recurring Whirlpool runs-constantly pattern we see across Toronto is a frosted rear evaporator from a dead defrost circuit - an open WP12729128 heater or a stuck-open WPW10225581 bimetal - on top-mount and bottom-mount cabinets, with adaptive-defrost (Jazz-board WPW10503278) units showing the relay-stuck-on variant where the compressor never cycles off. A close second is the mechanical pair: dust/pet-hair-caked condenser coils plus a tired condenser fan W10124096 in cramped galley-kitchen installs where the rear gets no airflow.
• We roll to these calls with the defrost heater WP12729128, bimetal thermostat WPW10225581, evaporator fan W10189703 and the condenser fan kit W10124096 (blade + harness included) on the van, plus the W10899382 damper/diffuser and a thermistor for the over-cooling/stuck-open variant - the shared Whirlpool/Amana/Inglis/KitchenAid parts book means one stock kit covers most badges same-day; only the WPW10503278 Jazz board and WPW10312695 main board are order-in and need serial-plate programming.

For the full Whirlpool refrigerator module — every fault, part number and code — see Whirlpool refrigerator repair in Toronto, and for the same fault across all brands the refrigerator running constantly / never shuts off guide.