I have a new heating system and combi boiler (less than 1 year old) The radiator in my lounge (nearest to the boiler) is cold at the bottom and warm at the top. I read that this could be a problem with the balancing and wanted clarification. All radiators are fitted with TRV's. All other rads are regular and were provided by my plumber except the lounge radiator which is a 'fashion' radiator - like an old school column rad that I bought from B+Q...
you may have already sorted the problem,but if not I suspect as the system is new and the rest of the rads are fine it could be the TRV on that rad which is faulty,you could try and take the top off the TRV you should see a needle sticking up it may be stuck try to move it up and down do not use a lot of muscle power if it is stuck spray some plus gas on it try a pair of pliers on it do not bend it,if you can free it fine if not get a new valve.
Best Regards