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critical Drayton

Error Code E2

External sensor fault — indicates a problem with the external temperature sensor connection.

? What Causes This

Fault or failure of the external sensor connections. Check the connections at the terminal block.

How to Fix It

  1. Verify that the external temperature sensor is properly connected.
  2. If no issues found, replace the Digistat+2 thermostat.

Source: page 2 of the official manual

From the manual

Manual page 2 — Drayton error E2

This error code appears in:

Drayton Digistat 2