Dishwasher
E1
The E1 error code on a Siemens dishwasher indicates a water heating fault — the appliance cannot reach the target temperature within the expected time. It’s a moderately serious fault that will stop wash cycles from completing properly, but in many cases it’s fixable without a professional.
What does this error mean?
Your Siemens dishwasher monitors water temperature throughout each cycle. The E1 code is triggered when the water fails to heat up to the required temperature within a set time window — typically detected by the NTC temperature sensor or caused by a failed heating element. The machine stops the cycle to protect itself and your dishes from an ineffective, cold wash.
Est. repair cost
£10–£50 DIY (NTC sensor or heating element parts); £80–£160 professional repair; £150–£250+ if control board replacement is needed
🔍 Likely causes
🛠️ Step-by-step fix
Reset the machine first: turn it off at the mains, wait 60 seconds, then switch it back on and start a new cycle. A one-off glitch can occasionally trigger E1.
Check the water inlet temperature: if your home’s cold water supply is very cold (common in winter), run the hot tap nearest the dishwasher for 30 seconds before starting a cycle to prime warm water to the appliance.
Inspect and clean the filter and spray arms: a heavily blocked filter forces the heating element to work harder and can contribute to heating faults. Remove, rinse, and refit the filter assembly.
Test the NTC temperature sensor: if you’re comfortable using a multimeter, the NTC sensor (located inside the sump area) should show around 6,000–12,000 ohms resistance at room temperature. A reading of zero or infinite resistance confirms a failed sensor — replacement parts cost £10–£25.
Check the heating element: with the machine unplugged and the lower panel carefully removed, test the element terminals with a multimeter. You should see 20–30 ohms resistance. An open circuit (infinite reading) means the element has failed and needs replacing — a common DIY repair with parts available for £20–£50.
If none of the above resolves the fault, stop DIY work — a control board fault or internal wiring issue requires a qualified appliance engineer.
📞 When to call a professional
If replacing the NTC sensor or heating element doesn’t clear the E1 code, call a qualified appliance engineer — the fault likely lies in the wiring loom or control board, which require specialist diagnosis. When booking, tell the engineer the exact error code (E1), your machine’s model number (found on the inner door frame), and which steps you’ve already tried. Expect a call-out and diagnosis fee of £60–£90.
⚖️ Repair or replace?
A heating element or NTC sensor replacement by a professional typically costs £80–£160 all-in, which is worth doing if your Siemens dishwasher is under 8 years old. If the machine is older than 8–10 years and the fault is a control board (£150–£250+ in parts alone), replacement is likely the more cost-effective option. A new mid-range Siemens dishwasher starts at around £450–£600 in the UK.