Dishwasher
E7
The E7 error code on a Miele dishwasher indicates a fault with the flow heater or its temperature sensor — it’s a moderate-to-serious fault that will stop your machine from completing a wash cycle.
What does this error mean?
Miele’s E7 code signals that the dishwasher’s flow heater (also called the continuous flow heater) is not reaching or maintaining the correct water temperature during the wash or rinse phase. The machine’s control board monitors the heating element and NTC temperature sensor, and triggers E7 when the temperature doesn’t rise as expected within a set time. This could mean the heater itself has failed, the sensor is giving a false reading, or there’s an electrical supply issue to the heating circuit.
Est. repair cost
£15–£30 DIY NTC sensor replacement; £80–£180 professional repair for heater or sensor; £150–£250+ for control board replacement
🔍 Likely causes
🛠️ Step-by-step fix
Reset the machine: turn it off at the mains, wait 30 seconds, and restart a short cycle. A one-off E7 can sometimes be caused by a temporary sensor glitch that clears on reboot.
Check and clean the filter and spray arms: a blocked filter restricts water flow to the heater. Remove the bottom filter basket, rinse it under the tap, and clear any debris from the spray arm holes with a cocktail stick.
Run a hot descaling cycle: if you live in a hard water area and haven’t descaled recently, pour a dishwasher descaler (e.g. Finish Dishwasher Cleaner) into the base of the empty machine and run the hottest cycle available. Limescale coating on the heater can trigger E7.
Check the salt reservoir: Miele dishwashers rely on correct salt levels to soften water and protect the heater. Refill the salt reservoir if the indicator light is on, then run a short cycle to check if the error clears.
Inspect the NTC temperature sensor (competent DIYers only): if you’re comfortable removing the kick plate and side panel, the NTC sensor is a small two-wire probe clipped to the heater. Test it with a multimeter — a healthy NTC reads around 4,000–6,000 ohms at room temperature. A reading of zero or infinity means it needs replacing (typically £15–£30 for the part).
Do not attempt to replace the flow heater yourself unless you are a qualified electrician: the heater is mains-connected, involves draining water from internal components, and requires the machine to be fully dismantled. This is a job for a professional.
📞 When to call a professional
If the error persists after resetting, descaling, and cleaning the filters, call a Miele-approved or reputable local appliance engineer. Tell them you have an E7 fault and that you’ve already ruled out limescale and a sensor glitch — this saves diagnostic time. You’ll need a professional if the flow heater element, thermal cutout, or control board needs replacing.
⚖️ Repair or replace?
A professional repair for an E7 fault typically costs £80–£180 in the UK, depending on whether it’s the sensor (cheaper) or the full heater assembly (more expensive). Miele dishwashers are built to last 20 years, so if your machine is under 10 years old, repair is almost always worth it. If it’s over 12–15 years old and facing a heater replacement, weigh the repair cost against a new mid-range Miele (from around £700) — a new machine may be the smarter long-term investment.