What E42 Means
E42 is one of the two error numbers behind the F2 message. Wolf's CSO24 Convection Steam Oven Service Manual defines it as the water temperature sensor reading too high a resistance - an implausibly cold value - and attributes it to a break or loose contact in that sensor or its wiring. Its companion, E41, is the shorted version, and that one carries a leaking boiler among its causes.
Common Causes of E42
- A break or loose contact in the water temperature sensor wiring
- A water temperature sensor that has failed open
- A connector at the boiler that has corroded or worked loose in a humid cabinet
🔧 One Safe Check You Can Try
Check underneath and behind the appliance for any sign of water, and whether the cabinet floor beneath it is damp. Even though E42 itself points at a break rather than a leak, the sensor it names sits at the boiler, and finding water early is always worth the two minutes.
⚠ Why You Shouldn't Go Further Than That
- The sensor is mounted on the boiler inside a cabinet that carries both water and live electrical parts, so the appliance goes off at the breaker before anything is opened.
- Corrosion in a humid cabinet can affect more than one connector, which is why a technician inspects the harness rather than reseating the one that failed.
- Replacing a sensor without finding why its connection failed usually means the replacement fails the same way.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.