E178 — Low temperature safety thermostat tripped

What does E178 mean?

The low temperature safety thermostat has tripped, indicating that the boiler or system water temperature is too low for safe operation or has dropped unexpectedly.

• Faulty low temperature safety thermostat or sensor.
• Poor water circulation in the system.
• Blocked or jammed pump.

Click steps to track your progress.

1. 1

   Turn off the main power supply to the boiler, wait 30 seconds, then turn it back on.

2. 2

   Ensure all heating system valves are fully open.

3. 3

   Check the system water pressure on the boiler's gauge.

4. 4

   If the error persists, a qualified technician should check the sensor and the water circulation system.