Fault 40 Code 102 — Temperature sensor T1 faulty, break in sensor lead

What does Fault 40 102 mean?

The Worcester Bosch Greenstar CDi Boiler displays Fault 40 with code 102, indicating a break in the sensor lead for temperature sensor T1, which is on collector group 1.

• Break or interruption in the sensor lead (T1)
• Loose or disconnected wiring for sensor T1
• Faulty temperature sensor T1

Click steps to track your progress.

1. 1

   Visually inspect the entire length of the sensor lead for T1 for any breaks, cuts, or disconnections.

2. 2

   Ensure the lead is securely connected at both ends.

3. 3

   If a break is found or the fault persists, contact a qualified heating engineer to check and replace temperature sensor T1 if necessary.