Setting a central heating bypass valve involves adjusting it to maintain adequate flow through the system when thermostatic radiator valves (TRVs) close down. The goal is to prevent the boiler from short-cycling and ensure efficient heating. Here's how to adjust it:
-
Heat the System: Ensure your central heating is running at full capacity. This means all radiators should be calling for heat.
-
Initial Adjustment: Begin by finding the adjustment knob on your bypass valve.
-
Reduce Setting: Gradually turn the adjustment knob towards 0.1 bar.
-
Monitor the Outlet Pipe: Carefully feel the outlet pipe from the bypass valve. According to our reference, you should turn the adjustment knob towards 0.1 bar "until you begin to feel the outlet pipe from the bypass valve begin to feel warm."
-
Fine-Tune: Once you feel the heat, turn the setting back towards 0.5 bar by half a turn. The reference states to turn it back "to prevent constant flow". This prevents the bypass valve from being constantly open, which would waste energy.
Therefore, while the system is heating at full capacity, gradually turn the adjustment knob of the bypass valve towards 0.1 bar until you begin to feel the outlet pipe from the bypass valve begin to feel warm. Once this heat is felt, turn the setting back towards 0.5 bar by half a turn to prevent constant flow.
