people may wish to get a plumber in to do the job at this point.
if your radiator is only warm at the bottom, then the most common problem is that the radiator has air in it and it needs to be ‘bled’. bleeding a radiator is simply the process of letting the trapped air escape from the radiator. cold spots on the radiator are normally caused by this trapped air. it’s fairly common to have to bleed a radiator from time to time, therefore it is a good idea to learn how to do it since calling out a plumber to fix this common and simple issue is not very 