GE Wall Oven Repair in Toronto — Not reaching or holding temperature (uneven baking)

• Drifted oven sensor (RTD WB21X5301, AP2023670; PS236043) is the leading not-reaching-temp fault on GE electric ovens that run cold rather than dead. It is a platinum RTD that should read about 1080-1100 ohms at room temperature unplugged (~1100 at 77F); as the coil ages high, the control 'sees' the cavity as hotter than it is and under-feeds the elements, so the oven stalls low or slowly drifts down mid-bake. We meter it cold against the GE RTD curve, and anything off the curve means the WB21X5301 gets replaced, not recalibrated. On GE this surfaces as an F3 (open sensor circuit) or F4 (shorted) only when the resistance is fully out of circuit; a sensor that is merely drifted often runs cold with no code at all.
• A weak bake element WB44T10011 (AP2030997; PS249286, supersedes 820921 / WB44T10059) makes a GE oven preheat then fall short of setpoint, distinct from a fully open element that gives a flat no-heat. GE's own preheat logic runs the broil element AND the bake element together to heat fast, then drops the broil at setpoint - so an element that is degrading but not yet open lets preheat 'almost' get there while the broil assists, then sags below setpoint once the cavity has to hold on the bake element alone. The tell is an element that won't glow fully red and ohms high/out of range; we confirm continuity and resistance at the terminals before pricing electronics.
• On gas GE ovens the runs-cold / never-fully-hot story is a weak oven igniter: the flat WB13K21 (AP2020569; PS231280) or the round glow-bar WB2X9154 (AP2014008; PS243425) by model. As the igniter ages its resistance climbs and current falls, so it glows orange for 90 seconds or more but no longer draws enough current to open the gas safety valve - the burner lights late, cycles weakly, or never fully establishes, so the cavity runs cold. Healthy draw is igniter-style-dependent: roughly 3.2-3.6A on the flat WB13K21 and only about 2.5-3.0A on the round WB2X9154, so we amp-clamp the igniter while it glows and compare the reading against the valve rating for that model rather than one fixed number - a draw below the model's spec confirms a weak igniter, while a sufficient draw with no/poor flame points at the gas safety valve instead.
• Bake element and sensor both test good but the oven still won't reach setpoint points at the bake relay on the GE control board (ERC) failing to cleanly close the 240V leg - GE flags 'oven won't heat' as the most common reason this board is replaced, with relay wear from heavy use a known mode. The board is the WB27T-family ERC, e.g. WB27T11311 (supersedes WB27T10467 / WB27T10816 / WB27T11273) on TrueTemp-era ranges, or a newer-generation control by model/serial. A worn relay may close intermittently, so the element fires weakly and the cavity creeps up but never holds setpoint. We meter AC voltage at the element terminals during a bake call before condemning the board - a board is the last honest suspect on an under-heat, not the first.
• A corroded or loose sensor-harness connection is its own runs-cold fault, separate from the RTD itself. Added resistance in that circuit stacks onto the WB21X5301's reading, so the control sees a higher number than the real cavity temperature and under-heats the food - the food comes out pale and undercooked even though the display claims it hit temperature. On GE we clean and re-seat the sensor connector at the rear wall and re-meter end-to-end before anyone buys a sensor, because it is a frequent false-positive on RTD swaps.
• When a GE oven runs only mildly cold, it is often built-in calibration drift, not a failed part. GE's OFSt offset is reached by holding Bake + Broil for ~2-3 seconds (SF/Special Features), and it trims only +/-35F - it adjusts bake and does not touch broil or self-clean. We bring a calibrated oven thermometer and read the stabilized average ~20 minutes after preheat: a 10-20F miss is a calibration tweak, but an oven off by MORE than 35F physically cannot be dialed out and the real cause is the RTD WB21X5301 or the control board, not a 'setting.'
• Sensor placement is a quiet cause of 'never gets hot enough' on GE: an RTD bent against the rear wall or touching a rack or element reads localized heat instead of cavity air, so the control satisfies early and the bake side undershoots even with a healthy WB21X5301. We verify the probe sits proud off the back wall on its two screws and isn't shorting to metal before changing parts - it's a no-part fix on a real subset of under-heat calls.

GE not reaching or holding temperature (uneven baking) in Toronto — the local specifics

• The recurring GE-in-Toronto pattern on not-reaching-temp is the 'it says it preheated but my food comes out pale and underdone' call - and on GE that splits cleanly two ways: a drifted WB21X5301 sensor making the control quit early (often with no code), or a tired WB44T10011-family bake element that lets the broil assist carry preheat then sags once the bake element has to hold setpoint alone. We see the 'runs cold with no error code' version far more than owners expect, because GE only throws F3/F4 when the sensor is fully open or shorted, not when it has merely drifted high.
• We carry the WB21X5301 oven sensor and the WB44T10011-family bake element to every cold-running GE call (plus the WB13K21 / WB2X9154 igniters on gas models), a calibrated oven thermometer to separate an in-range OFSt offset from a real fault, and an amp clamp to settle igniter-vs-valve on gas - the WB27T-family control board is staged from the distributor only after metering at the element terminals proves the relay, not guessed on day one.

For the full GE wall oven module — every fault, part number and code — see GE wall oven repair in Toronto, and for the same fault across all brands the wall oven not reaching or holding temperature (uneven baking) guide.