Hoval
Poor Heat Distribution / Sludge Blockage
Radiators only warm at the top or some radiators stay cold while boiler runs
Advertisements
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.
Advertisements
Possible Causes
Sludge buildup in radiators and pipework, Blocked return filter or strainer near Hoval boiler, Incorrect system balancing, Pump not providing sufficient flow
How to Fix / Troubleshooting
Safety: Surfaces may be hot. Allow radiators to cool before removing bleed screws.
- Bleed radiators: Release trapped air from all radiators, starting with the highest. Top up system pressure afterwards.
- Clean strainers: Isolate and clean any Y-strainers or filters on the return to the boiler. Remove sludge and reinstall.
- Balance system: Partially close lockshield valves on radiators that heat quickly to force more flow to colder radiators.
- System flush: If sludge is heavy (black water, repeated blockages), arrange a professional power flush and consider fitting a magnetic filter on the Hoval boiler return.
Advertisements
Repair Difficulty
Medium
3/5
Required Part
System Strainer / Magnetic Filter
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements