E9 — Safety temperature limiter tripped

What does E9 mean?

The safety temperature limiter in the central heating (CH) flow has tripped. This is a critical safety measure, often due to high system pressure or an overheating issue.

• Overheating of the central heating system.
• High system pressure.
• Defective safety temperature limiter.
• Restricted water flow.

Click steps to track your progress.

1. 1

   Check your boiler's pressure gauge; if it's too high, you may need to bleed radiators or drain some water.

2. 2

   Ensure all radiator valves are fully open to allow water circulation.

3. 3

   Reset the boiler using the reset button or by cycling the power.

4. 4

   If the issue persists, contact a Gas Safe registered engineer for inspection.