service 20

[Charbot6]

I have a grohtherm wireless shower, when I turn it on there is no water coming out and it shows service 20 on the remote. Has anyone got a solutions for it thanks

 

[thompsonbrown]

Hi & welcome.
service 20 fault is pump protection for the pump. usually caused by lack of water either blocked inlet filter or sticking non-rtn valve. also check your service isolation valves are fully open.