Dishwasher
E13
The E13 error code on a Bosch dishwasher indicates the water temperature in the machine has risen too high — typically above 75°C — which triggers a safety cutout. It’s a moderately serious fault that will stop the cycle, but it’s often fixable at home without a call-out.
What does this error mean?
Your Bosch dishwasher continuously monitors water temperature throughout each cycle using a thermistor (temperature sensor). The E13 code fires when the sensor detects water that is dangerously hot — usually caused by incoming water from your hot supply being far too warm, or a fault with the heating circuit that’s preventing accurate temperature regulation. The machine shuts down to protect internal components and prevent a safety hazard.
Est. repair cost
£80–£160 professional repair (thermistor or element); £10–£25 DIY thermistor part only
🔍 Likely causes
🛠️ Step-by-step fix
Reset the dishwasher first: Turn it off at the mains, wait 60 seconds, then power it back on and run a short cycle. A one-off temperature spike can trigger E13 without an underlying fault.
Check your water supply connection: Locate the inlet hose at the back of the machine (usually bottom-left). Confirm it is connected to the cold water stop tap, not the hot. If it’s on the hot supply, switch it over — this is the single most common cause of E13.
Run your kitchen cold tap and feel the temperature: If the cold water coming out feels warm (above 25°C), your plumbing may have a crossed connection or your pipes may be running too close to the boiler. Call a plumber.
Check the inlet hose routing: Make sure the cold inlet hose isn’t pressed against a hot water pipe or the side of the boiler cupboard. Reroute or insulate if necessary.
Test the thermistor (DIY with a multimeter — only if you’re confident): After disconnecting the machine from the mains, the NTC thermistor is located on the sump assembly at the base of the tub. At room temperature (~20°C) it should read approximately 12–16 kΩ. A wildly different reading indicates a faulty sensor. Replacement thermistors cost £10–£25 online — search your model number plus ‘NTC sensor’.
If the above steps don’t resolve the fault, do not attempt to open the control board or heating element circuit yourself — these require a qualified appliance engineer.
📞 When to call a professional
Call an engineer if the error persists after confirming a cold water supply connection and completing a reset, as the fault likely lies with the thermistor, heating element, or PCB — all of which require component testing with specialist tools. When booking, tell the engineer: ‘My Bosch dishwasher is showing error code E13 — I’ve confirmed it’s on a cold supply and a reset hasn’t cleared it.’ Expect a diagnostic visit charge of £60–£90 before any parts.
⚖️ Repair or replace?
A thermistor replacement typically costs £80–£130 all-in with a call-out; a heating element runs £100–£160; a PCB replacement can reach £180–£250, which may not be economical. As a rule of thumb, if your Bosch dishwasher is under 8 years old and the repair quote is under £150, repair is worthwhile — Bosch machines are well-built and parts are widely available. If it’s over 10 years old and facing a PCB fault, a new mid-range Bosch dishwasher (£350–£550) is likely the better long-term investment.