Why are my radiators dodgy? had a investigational system put in going on for two years ago...

had a investigational system put in going on for two years ago all fine have them serviced a couple of months ago again fine but for some reason presently when they come on none of the downstairs work unless i turn off adjectives rads upstairs and then when warm up go rear and turn them all on upstairs they dont call for bleeding and my pressure is ok so what could be wrong?
My garage door isn't working right?
Answers:    Sounds like any the system isn't balanced correctly, sludge within the system, (most new systems are not cleaned properly unfortunately) or both. You can harmonize using the valve next to a plain cap, bear it off and turn respectively (hot) radiator down half a turn, walk out half hour and do duplicate again (only turn hot ones down), etc untill all are hot. There is a possibility that the pump speed is wrong, this should hold been set at installation, so unless someone have touched it, it should be the same, listen to the pump and be sure it is a steady nouns, not an alternating sound, this would also indicate a blockage or thin pump.
What can I use to verbs my drive...
pl. approach a best service man. perhaps some parts may necessitate replacing. we can't say when what will jump wrong.