Why balance?
Water takes the easiest path. Radiators closest to the pump get lots of hot water; the furthest get little. Balancing slightly restricts the near ones so the far ones get their share.
Know your valves
- Lockshield valve: plastic cap, adjusted with a key or spanner. Sets the flow — the balancing valve.
- Wheelhead or TRV: the one you turn by hand to control the room.
Step by step
- Bleed all radiators first.
- Turn the heating off and let it cool.
- Open all TRVs and lockshields fully.
- Turn on the heating and note the order radiators warm up.
- Turn off the heating, let it cool.
- For the first radiator to warm, close the lockshield then open it about a quarter turn.
- Open the next ones a little more each time, and leave the last ones fully open.
- Run the heating and adjust until all heat well.
Pro tip: With a pipe thermometer, aim for about 12°C between the pipe going in and the pipe coming out of each radiator.
Still not right?
Sludge, a weak pump or undersized pipes can stop good balancing. Check those before spending hours adjusting.
