Power Flush London
Power Flush London Help Centre
What a power flush fixes, when you need one, and how to book a safe, effective clean.
We provide power flushing across London for cold radiators, noisy boilers and poor circulation.
Gas Safe registered engineers for safe boiler and heating system checks alongside the flush.
24/7 call handling with London wide booking and fast triage.
Power Flush London (Gas Safe)
Cold radiators, black water, noisy boiler, or repeated boiler faults? Tell us your postcode, number of radiators, and your main symptom and we will advise the right next step.
📞 Call 0203 695 3137
Request Call Back
Fast triage: postcode, radiator count, system type (combi or cylinder), whether radiators are cold at the bottom, and whether you have any boiler fault codes.
⚠️ Safety First
Boiler in lockout? Do not keep resetting it. Note the fault code and call us. We can advise whether the issue is circulation, pressure, or a component fault.
Water leaking? If there is a leak, we will advise repairs before flushing. Flushing a leaking system can make things worse.
Magnetic sludge and limescale: Power flushing removes heating system sludge (magnetite). A separate scale treatment may be required for hard water scale in certain components.
Jump to: Symptoms · What a Power Flush Is · How It Works · Aftercare · FAQs
Signs You May Need a Power Flush
- Radiators cold at the bottom and warm at the top
- Some radiators not heating even after bleeding
- Noisy boiler (kettling, banging, gurgling)
- Boiler overheating or showing circulation faults
- Dirty black water when bleeding radiators
- Heat takes ages to reach upstairs or far rooms
What a Power Flush Is
A power flush is a deep clean of your central heating system using a specialist machine, controlled water flow, and cleaning chemicals to remove magnetite sludge, debris and circulation blockages. It can improve heat distribution and reduce strain on your boiler, pump and pipework.
How Power Flushing Works
- System assessment: we check your symptoms, boiler type, and radiator condition.
- Machine connection: we connect the power flush unit to the system safely.
- Clean and agitate: each radiator is flushed individually to lift sludge.
- Neutralise and rinse: we flush until the water runs clear.
- Protection added: inhibitor is added to reduce future corrosion.
- Filter advice: we recommend magnetic filtration where suitable.
What a Power Flush Can Fix (and What It Cannot)
Power flushing can help with: cold radiators, uneven heat, circulation faults, noisy pump operation, boiler overheating caused by restricted flow.
Power flushing cannot fix: broken pumps, faulty zone valves, failed diverter valves, or internal boiler component faults that need replacement. In those cases, we advise repairs first, then flush if needed.
Aftercare and Prevention
- Use inhibitor: helps prevent corrosion and sludge returning.
- Consider a magnetic filter: catches debris before it reaches the boiler.
- Annual boiler servicing: helps spot circulation issues early.
- Bleed radiators properly: and repressurise if needed.
If your boiler pressure keeps dropping, use our pressure guide.
🔧 Boiler Fault Codes and Cold Radiators?
If you are seeing ignition or overheat faults alongside cold radiators, the underlying problem can be circulation and debris. A power flush is often the right next step once safety checks are complete. If you are unsure, start with a call back request and we will advise.
Power Flush FAQs
How long does a power flush take?
Most systems take several hours depending on radiator count, access, and how contaminated the system is.
Will a power flush stop boiler breakdowns?
It can reduce breakdown risk caused by poor circulation and sludge, but it cannot prevent failures of worn components.
Do I need a power flush when fitting a new boiler?
Often yes, especially if the system is older. A clean system helps protect the new boiler and improves efficiency.
Will it make the system leak?
Flushing does not create leaks, but it can reveal existing weak points. If you suspect a leak, tell us before booking.
How much does a power flush cost?
Cost depends mainly on radiator count, access, and how contaminated the system is. Tell us how many radiators you have and your postcode and we will advise the best approach for your system.
Do I need a magnetic filter after a power flush?
A magnetic filter is often recommended, especially on older systems, to catch debris before it reaches the boiler. We will advise what is suitable for your system.
Related Services
Book a Power Flush
Speak to our team and we will advise if a power flush is right for your system.
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