Keston Poor Central Heating Circulation

Boiler runs but radiators do not get hot or only partially heat up

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Sludge in radiators, Airlocks in system, Pump running at low speed, Blocked system filter

How to Fix / Troubleshooting

Safety: Radiators and pipes can become very hot. Use caution when bleeding or touching them.

User actions:

Bleed air from the highest radiators using a radiator key, then recheck boiler pressure and top up if needed.
Ensure all radiator valves are open and that no TRVs are stuck in the closed position.
Check that the room thermostat is set high enough and that time controls are calling for heat.

Engineer actions:

Check the Keston circulation pump for correct operation and speed setting; increase speed if necessary.
Clean or replace any system filter or strainer on the return to the boiler.
Balance the heating system by adjusting lockshield valves to ensure even heat distribution.
Powerflush the system if sludge is restricting flow.

Repair Difficulty

Medium 3/5

Required Part

Circulation Pump Assembly

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