Boiler serviced or Rads serviced .. Which first?

Hi All
My oil boiler needs to be serviced as do my radiators. None of the radiators in the house heat up 100%. Most of them stay cool at the bottom even when I bleed them. I want to get them flushed out. Which should I service first, the boiler or the rads? Or would the chap who services the boiler also do the rads?

Thanks in advance
t

Powerflushing is pretty specialist. Make sure the boiler service person is OFTEC registered/certified and you get a full flue gas analysis print out.

What area are you in?