13/03/2026
Cold radiator solved today (weird one) 🥶➡️🔥
Had a call-out for a cold radiator that wouldn’t heat up properly. Turned out there was a bit of felt/debris lodged in the valve/connection (see pics) — something that definitely shouldn’t be in a heating system. It was restricting flow, so the rad never stood a chance.
While diagnosing, we also found the circulation pump had failed, so that was replaced too. System back up and running and rads heating as they should.
Quick tip if you’ve got one cold radiator:
If the rad is cold but the pipes/other rads are warm, it’s often flow restriction (valve blockage, sludge, stuck pin, air, TRV issue).
If multiple rads are struggling / heating is patchy, it can be pump/flow or system sludge.
Posting in case it helps someone else — happy to point you in the right direction if you’re having similar symptoms (drop a comment/DM).