How to bleed a radiator
Worth doing before you call anybody out, and it costs nothing.
About 20 minutesTurn the heating off
Let the system cool completely, or you will be bled on by very hot water.
Find the valve
Top corner of the radiator, a small square socket facing sideways.
Open it a quarter turn
Hold a cloth under it. You will hear air. Stop when water arrives.
Check the pressure
Bleeding drops it. Top the boiler back up to the mark on the gauge.
