Boiler seems OK, the hot water is working fine. The pump was recently replaced incase that was the issue and it's whirring away.
The rads just aren't getting hot though. We've bled them, but even turning right up doesn't result in any heat. The first one on the system has got slightly warm, the rest are stone cold.
A new radiator was put on a few days ago (that's currently turned off), could that have caused it? We have had problems with the heating over the winter - the boiler is old and obviously struggling, but some of the rads would heat up - at the moment everything is just cold.
(can't believe I'm posting this in the middle of May.. ugh)