vaillant ecomax 824/2 e condensing boiler

[htg]

Dear HEATING ENGINEER,
I have a problem with the ECOMAX 824/2 E condensing boiler, as the hot water works, but the central heating does not work.

I have checked the divertor valve and the pins moves up and down.

I have checked physically and the pipes on the right hand side which goes to the heat exchanger they all get hot, bypass get hot, so i can not think of anything else. return pipes looks hot. The boiler reaches the temperature and then cut off, thinking the radiator water has reach the correct temperature.

Another engineer was saying the divertor valve it needs to be hookup.

Please advice