BAXI 105HE COMBI BOILER

[gewbe]

When all radiators are on fully some radiators are cold, If done seperatly they all work, No air in system, 12 radiators in total various sizes, it starts to change when more then 5 are on at the same time. could it be a dirty return filter slowing the the flow down or could the pump speed be altered. The return flow pipe at the boiler is always cold. This problem only accuried after radiators removed for extensive building and plaster work being done, A problem with debris in the system ? any help with this will be much apprecciated.
Cheers guys/ladys gewbe

 

[Baxi-Remeha]

could be dirt in the return filter, but suspect its more likely that when they took all the rads off the have upset the balance of the system. re balance the system and you should be ok....