Cause of error code E37

Contact for return sensor T2  open

Solution for error code E37

Check the data in Error mode. Boiler data during error:
1 Error  = 31
2 Operational status  = 00
3 Flow temp.  = 230
4 Return temp. = xx*
5 kW burner  = 00**
6 % pomp  = xx*
* = variable values
**= x3415=BTU/hr

Check the wiring. check the wiring for the sensor