central heating radiator problems

Hi all,

I was wondering if anyone would be able to help me. My dad drained down our central heating system with is a sealed system I believe with a boiler in the kitchen and a hot water storage tank in the upstairs cupboard. After he drained down the system and refilled it all the radiators up stairs are working but none of the downstairs are. The pipes from the boiler run upstairs first then drop down inside the walls to the downstairs rads. All the downstairs rads have a drain off point on them. Is this an airlock somewhere ?. Any help would be much appreciated.

Thanks Kevin.

Try turning off all the upstairs radiators, and run the heating this may force the water downstairs removing the airlock with it, keep an eye on the system pressure and be ready to re-charge it to 1-5 Bar if needed

Thanks Boilerman2 all try what you said as soon as I can. If that fails to help is it possible to pull the water through from one of the drain off points or will that do nothing ?