Bosch Error Code E22: What It Means and How to Fix
If your Bosch dryer shows E22, the control board has detected abnormal heating behavior — the drum temperature stays too low or rises too slowly. The most common cause is a faulty thermistor (temperature sensor), not a blown heating element. Replacing the element before testing the thermistor wastes time and money. Counter-intuitively, lint buildup inside the cabinet often overheats the thermistor and causes it to fail. Clean the lint path first, then test the sensor.
Five Fast Checks Before Opening the Dryer
Each of these checks takes under two minutes and may save you from pulling panels. Treat each item as a pass/fail decision and only move to the next check if the previous one passed.
- Lint filter clear? Remove it, hold it to light. If light hardly passes through, wash with soapy water and dry completely. Retest the dryer. If E22 returns, move to the next check.
- Exhaust duct blockage? Disconnect the duct from the back of the dryer. If you feel resistance when reaching inside or see lint clumps, clear the blockage with a vent brush. Run a test cycle. Duct clear? Proceed.
- Dryer reset passed? Unplug the dryer for exactly 10 minutes, then plug back in. If E22 disappears and the dryer heats normally, the error was a transient glitch. If E22 reappears, continue.
- No-heat cycle test? Set the dryer to air fluff (no heat). If the drum turns and no error appears, the heater circuit is likely fine, pointing to the sensor. If E22 shows even without heat, the issue may be in the control board wiring.
- Thermal fuse intact? Open the back panel and locate the thermal fuse (usually on the blower housing). Use a multimeter set to continuity — if the meter reads open (infinite ohms), the fuse has blown. Fix the underlying cause (airflow) then replace the fuse.
If any of these checks show a problem, fix it first and test again. If E22 returns, proceed to component testing. If you encounter similar sensor faults on other Bosch appliances, our guide covering common causes of e25 error on bosch dishwashing machine explains the diagnostic sequence.
Testing and Replacing the Faulty Components
You will need a multimeter, a screwdriver set (Phillips and Torx T20), safety gloves, and a flat pry tool.
Step 1: Unplug the Dryer and Access the Thermistor
The thermistor is usually located behind the lint filter housing or inside the rear panel. On most Bosch dryers, remove the top panel (two screws at the back, slide forward) or open the lower kickplate. Look for a small plastic probe with two wires connected to the main control board or heater assembly. Common mistake: pulling on the wires instead of the connector. Use a flat tool to gently release the tab.
Step 2: Test the Thermistor with a Multimeter
Set your multimeter to resistance (ohms). Disconnect the thermistor from the wiring harness. Expected values at room temperature (about 70°F / 21°C): between 10 kΩ and 15 kΩ. A good thermistor changes resistance smoothly when warmed — for example, by holding it in your hand. A shorted or open circuit (0 or infinite ohms) means the sensor is dead. Pitfall: testing while the thermistor is still hot from a recent cycle gives false low readings. Let it cool to room temperature first.
Step 3: Replace a Faulty Thermistor
If the thermistor fails the ohms test, replace it. Order the exact Bosch part number — look on the old sensor or your model’s parts diagram. Installation tip: apply a tiny smear of thermal paste (optional) on the sensor face to improve heat transfer. Tighten the retaining screw gently — overtorquing cracks the plastic housing.
Step 4: Check the Heating Element (Only If the Thermistor Is Good)
If the thermistor passes, test the heating element. Disconnect its two wires and measure resistance — typically 10–30 Ω depending on model. Infinite ohms means the element is burned open. Replacing the element requires removing the rear panel and, on many models, the blower wheel. Take photos of the wiring layout before you unplug anything.
Step 5: Clean the Cabinet and Ductwork
While you have panels off, vacuum all lint from inside the cabinet, the blower housing, and the exhaust duct. Restricted airflow is the number one cause of repeat E22 failures.
Bosch recommends cleaning the lint filter after every load and inspecting the exhaust duct annually. A dirty dryer not only causes error codes but is a fire hazard. — Bosch Home Appliances Service Guide
Step 6: Run a Test Cycle to Confirm the Fix
Reassemble the dryer, plug it in, and select a timed high-heat cycle (e.g., 30 minutes). Listen for the heating element to click in within the first 2–3 minutes — you should feel warm air at the vent. Normal behavior: the error code does not reappear, the drum heats steadily, and the cycle completes without stopping. Common mistake: running a short air-fluff cycle that never activates the heater, leading you to think the fix failed. Let the cycle run at least 10 minutes on high heat. If E22 persists after following these checks and replacements, the broader troubleshooting guide for common bosch dishwasher problems and solutions covers cross-appliance diagnostic logic that may help.
When to Stop and Call a Professional
The table below helps you decide whether to continue DIY or escalate.
| Situation | Likely Cause | Recommended Action |
|---|---|---|
| Thermistor tests good but E22 returns after replacing element | Control board fault or wiring issue | Stop DIY – call a technician |
| Burning plastic smell or melted insulation observed | Internal short or severe overheating | Unplug immediately – requires professional diagnosis |
| Previous water leak near the dryer (e.g., from washing machine) | Moisture damage to board or sensor wiring | Complex repair – schedule service |
| E22 appears intermittently (works one load, then errors) | Loose or corroded thermistor connector | Re-seat connector firmly before replacing parts |
If you are uncomfortable using a multimeter or removing panels, skip the DIY and call a service pro. One misstep can damage the control board. For washing machine temperature faults, our resource on troubleshooting bosch washing machine problems solutions covers similar sensor-related issues across product lines.
Frequently Asked Questions
Q: Can I bypass the thermistor to clear E22?
No. Bypassing disables temperature safety circuits and can cause the dryer to overheat dangerously. Replace the faulty sensor.
Q: Why does E22 show even after replacing the sensor?
Check the wiring harness leading to the main board. A broken wire or corroded pin can mimic a sensor failure even if the new sensor is working correctly.
Q: Is error E22 the same on all Bosch models?
Yes, E22 generally indicates a heating circuit or temperature sensor fault across Bosch dryers and some front-load washers. Always confirm with your specific model’s manual for exact diagnostic steps.