UK No heating downstairs combi boiler

[Tucker61]

At my sons house, had 2 radiators downstairs that would never heat up, so thinking that the locks held valve was down, today we replaced the valves, but still got the same issue.

He has a glowworm ultracom cxi combi boiler, upstairs gets hot quite quickly, we have bled all radiators, and tried to balance the system, but to no avail.

He has a policy for boiler service and parts only. I think it is with utility warehouse.
Should he just call them out and see what they say, just call a local heating engineer out, or anything else that he should check first ?

 

[ShaunCorbs]

Is it just two downstairs / others ok downstairs

I’m guessing you mean you replaced the trvs ?

 

[Tucker61]

Is it just two downstairs / others ok downstairs

I’m guessing you mean you replaced the trvs ?

Yes to both.

Replaced trv and locksheild valve.

 

[ShaunCorbs]

Yes to both.

Replaced trv and locksheild valve.

Have you turned all but the non working rads off ?

 

[Tucker61]

Have you turned all but the non working rads off ?

Yes, by doing this we do get heat to the downstairs radiators.