downstairs radiators turn off when upstairs are on and Vice Versa

[ghoyland]

I seem to have this problem that my radiators stopped working. I realised when i turned some of them off others satrtied working. The position im in today after a month of this problem is that when i turn the raditors off upstairs the downstairs radiators are really hot. What do you think is causing this and is it a problem that i can easily rectify.

Also the system im not able to have hot water at the same time as Heating. The system has a three point diverter valve. could this be the cause or could i have more than one problem. Any help and advice woud be really appreciative.
many thanks

GH🙄

 

[Puddle]

Could be valve not opening to heating correctly,try opening in mid postion manually if possible or maybe pump on its way out

 

[ghoyland]

Thank you very much. will let you know how that goes.

regards
Gary

 

[ghoyland]

Hi. i have checked the three port valve and the pump seems to be fine. This problem is puzzling me as the when i turn the upstairs radiators on the downstairs go of and this still happens. even then some of the downstairs radiators are getting bearly warm. is there anything else you feel i can check.

The diverter valve doesn't have a manual override so i can change the valve position. The pump was on the highest setting which i think wasn't right for microbore system.

thanks