New Radiators not heating up

[Queeny]

As part of our house renovation we had three new radiators fitted. They were taking with 2 hours to heat up, I've managed to fix this on 2 of the 3 radiators but one of them is still very slow to heat up.

I've noticed the fitting on the bottom of this radiator is different to the other two even though they are exactly the same radiator - could this be the problem? Here is the problem one

Here is one that is now working fine.

Thanks in advance for your help.

Dave

 

[PrenticeBoyofDerry]

Have you vented the radiator and you may also need to balance the system by tweaking the other valves on the other radiators in the house. By turning them down a little.