
Boiler repair & heating
Central heating power flush across London
Cold radiators with chilly bottom edges, brown sludgy water when you bleed them, or a boiler making kettling noises mean your heating is clogged. Our Gas Safe engineers cover London and the M25, typically reaching emergencies in 30 to 60 minutes to power flush the system clean.
Power flushing is the single most effective intervention to extend the life of an existing central heating system. Black iron-oxide sludge accumulates over years inside radiators, pipework and the boiler heat exchanger, restricting flow, reducing radiator output (you'll feel it as cold spots at the bottom), causing boiler 'kettling' noises, and accelerating component wear. A proper power flush removes virtually all of it.
We use professional Magnacleanse or Kamco power-flush rigs, high-flow circulator pumps, magnetic separators capable of capturing tens of grams of iron oxide per pass, and a sequence of cleaning chemicals (Sentinel X400 sludge remover, Sentinel X800 jetflo, fresh inhibitor X100). Every flush is followed by inhibitor dosing and a magnetic system filter installation to keep future sludge build-up under control.
Where this service applies
- ✅ Cold spots on radiators (particularly bottom edge), classic sludge symptom
- ✅ Boiler kettling noises (limescale and sludge on heat exchanger)
- ✅ Brown / black water when bleeding radiators
- ✅ Magnetic filter filling rapidly between services
- ✅ Before fitting a new boiler, required by manufacturers for warranty
- ✅ Pre-power-flush as part of a heating system upgrade
- ✅ Underfloor heating systems with reduced output
- ✅ After contamination event (e.g. sludge ingress from old galvanised tanks)
How we deliver
No surprises, no upselling. The exact path every job follows.
-
1Pre-flush system survey
Engineer inspects boiler, radiators, pump, pipework. Photographs sludge symptoms. -
2Magnacleanse rig installed
Connected at the boiler, pump, magnetic separator, dosing port. -
3Sludge remover dosed
Sentinel X400 introduced. Circulated through the entire system at high flow. -
4Per-radiator agitation
Each radiator individually flushed with chemical agitation. Valves and pipework reverse-flushed. -
5Final clean and rinse
Fresh water flushes until run-off is clear. -
6Inhibitor dosed
Sentinel X100 inhibitor introduced to fresh water, protects against future corrosion. -
7Magnetic system filter fitted
Adey MagnaClean or Fernox TF1 fitted on return line, catches residual sludge. -
8System recommissioned
Pressure-tested, vented, balanced. Final FGA on boiler.
Your questions answered
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Need a 24/7 emergency engineer?
30 to 60 minute response across every London borough. Gas Safe registered. 12-month workmanship guarantee.
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Need central heating power flush now?
30 to 60 minute response across every London borough. Gas Safe registered. 12-month workmanship guarantee.
