We may have found other answers which could help you.
Click here for Error Heat BoilerCan I move the thermostat to another room?
Siemens rdh10rf thermostat?
siemens rwb9 connections to boiler?
I cannot locate my Siemens receiver?
Siemens RDJ10RF thermostat problem?
Thermostat issues- Siemens RDH10RF?