We may have found other answers which could help you.
Click here for Button Reset LightsThermostat issues- Siemens RDH10RF?
Siemens brtrf keep LOSING connection?
my rdh10rf siemans thermostat will not send signal to my boiler. ?
siemens rwb9 connections to boiler?
Have I got got a faulty programmer?
Rdh10 & RCR10/443-GB by seimens?