EN

Not heating: Codes, Causes & Fixes

When a dishwasher, washer, dryer or oven runs but doesn't heat, the usual suspects are the heating element, the temperature sensor (thermistor) that controls it, a safety thermal fuse or – in dryers – restricted airflow that trips the overheat protection. Error codes often distinguish between a sensor fault and a heater circuit fault, which helps decide what to test. Heating elements run on mains voltage, so replacement is a job for a technician unless you are qualified; for boilers see “No heat or hot water”.

71Codes
3.0Average severity
17%High or critical
41%DIY-friendly
Severity distributionSeverity distribution

Most viewed

U4 Daikin · Air Conditioner / Heat Pump The indoor unit has lost its data link with the outdoor unit, so the system can't cool or heat. Moderate E6 Mitsubishi Electric · Air Conditioner / Heat Pump The indoor unit isn't getting valid signals back from the outdoor unit over the S3 wire. Moderate D80 LG · Dryer LG Flow Sense detected restricted airflow in the vent. The dryer still runs, but lint buildup… Moderate HE Samsung · Dryer The Samsung dryer isn’t heating as expected – often no heat at all. Check power, gas supply… Moderate F2 GE Appliances · Oven / Range The control saw the oven running hotter than its safety limit and shut the heat off. High F3 Whirlpool · Oven / Range The control can't get a valid reading from the oven temperature sensor, so it won't heat… Moderate

All codes (61)

All Severity 3+ Severity 4+
E5 Gree · Air Conditioner / Heat Pump E5: the Gree unit drew more current than allowed – often because supply voltage sagged… Moderate E6 Mitsubishi Electric · Air Conditioner / Heat Pump The indoor unit isn't getting valid signals back from the outdoor unit over the S3 wire. Moderate E6 Gree · Air Conditioner / Heat Pump E6 means the Gree indoor and outdoor units have lost their data link, so cooling and heating… Moderate E63 Bosch · Dryer Bosch US lists E63 as a heating element failure. Check power and airflow, then have the heater… Moderate E64 Electrolux · Dryer The Electrolux dryer's control sees no proper current through the heating circuit. Usually… Moderate E7 Daikin · Air Conditioner / Heat Pump The outdoor fan failed to spin up, or its speed signal went wrong, so the outdoor unit shut… Moderate EL01 MRCOOL · Air Conditioner / Heat Pump The MRCOOL indoor and outdoor units have stopped exchanging data, so the compressor won't run. Moderate F1E0 Whirlpool · Oven / Range The oven's main electronic control failed its own self-check, so the range stops running… Moderate F1E4 Whirlpool · Microwave The microwave's control tried to run a function and failed – a control board, power relay… Moderate F1E5 Whirlpool · Microwave The high-voltage inverter or the magnetron isn't working – the microwave runs but doesn't heat… Moderate F2 GE Appliances · Oven / Range The control saw the oven running hotter than its safety limit and shut the heat off. High F20 Miele · Washing Machine The Miele couldn't heat the wash water in the time allowed. Usually a failed heater… Moderate F24 Miele · Dishwasher F24 flags the relay that switches Miele's water heater. Miele treats it as a technical fault… Moderate F3 Whirlpool · Oven / Range The control can't get a valid reading from the oven temperature sensor, so it won't heat… Moderate F8E0 Whirlpool · Oven / Range The oven's cooling fan is turning too slowly – from blocked airflow, a failing fan motor or its… Moderate F9 LG · Oven / Range LG's control saw the oven temperature rise too slowly after preheat began and shut the heating… Moderate F96 GE Appliances · Oven / Range GE says an internal part needs replacing; on wall ovens F96 usually means the upper cooling fan… Moderate F97 GE Appliances · Oven / Range On GE double wall ovens F97 usually means the cooling fan isn't spinning fast enough, so… Moderate F9E0 Whirlpool · Oven / Range The control sees the wrong supply voltage – usually neutral and a hot leg swapped at the cord… Moderate H11 Panasonic · Air Conditioner / Heat Pump H11: the Panasonic indoor unit stopped getting valid signals from the outdoor unit after it… Moderate HC Samsung · Dryer The Samsung dryer sensed air above its safe temperature limit and cut the heat. Airflow… Moderate HE Samsung · Dryer The Samsung dryer isn’t heating as expected – often no heat at all. Check power, gas supply… Moderate L5 Daikin · Air Conditioner / Heat Pump L5: the outdoor inverter saw a current spike on the compressor output and shut the compressor… High P1 MRCOOL · Air Conditioner / Heat Pump The outdoor unit saw supply voltage too high or too low and stopped the compressor to protect… Moderate P4 Midea · Air Conditioner / Heat Pump P4 (PC 04 on newer displays): the outdoor board couldn't drive the inverter compressor… High P8 Mitsubishi Electric · Air Conditioner / Heat Pump The indoor coil isn't getting colder (or warmer) than the room after the compressor starts, so… Moderate tE Samsung · Dryer The Samsung dryer can't trust its temperature reading. Clean the lint screen and vent, then… Moderate tE1 LG · Dryer The LG dryer's thermistor circuit is reading open or out of range, so the control shuts off… Moderate U0 Daikin · Air Conditioner / Heat Pump The outdoor unit has judged the system to be low on refrigerant and stopped the compressor… High U4 Daikin · Air Conditioner / Heat Pump The indoor unit has lost its data link with the outdoor unit, so the system can't cool or heat. Moderate

Symptoms

Won't start a program 55Not cooling 41Leaking water 17Not draining 16Not filling with water 14Door won't lock or open 13No heat or hot water 11Not spinning 9Low system pressure 1