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Specialist Service

Power Flush London

Central heating power flushing across all London boroughs. Remove sludge and scale, restore full efficiency, extend boiler life. Includes inhibitor treatment and magnetic filter.

From £299 - fixed price, all inclusive

0800 123 4567
Quick Answer

A power flush in London costs £300–£600 depending on system size (number of radiators). The process takes 6–8 hours and restores heating efficiency by removing sludge and debris from your system.

Power Flush Cost London - 2026 Prices

Job TypeTypical CostTime
Power flush - up to 6 radiators£300–£4004–6 hours
Power flush - 7–10 radiators£400–£5006–8 hours
Power flush - 11–15 radiators£500–£6008–10 hours
Power flush + inhibitor dose£350–£6506–10 hours
Magnetic filter installation£150–£2501–2 hours
System flush without power flush£150–£2502–3 hours

* Prices are estimates for London. Fixed price confirmed before work begins. £60 call-out fee.

Signs Your System Needs a Power Flush

  • Radiators cold in patches or slow to heat
  • Boiler making banging or kettling noises
  • Frequent boiler breakdowns
  • Heating system slow to reach temperature
  • Dark or discoloured water when bleeding radiators
  • High energy bills despite adequate boiler size
  • Some radiators won't heat at all
  • Central heating pump failing regularly
1

Diagnostic Check

We test flow rates and temperature differentials across radiators to confirm sludge is the cause of the problem.

2

Power Flushing

High-velocity water with professional chemicals flushes through every radiator and circuit, removing all debris.

3

Inhibitor & Filter

We refill with clean water and Fernox or Sentinel inhibitor, then fit a magnetic filter to protect the system going forward.

New Boiler Installation?

If you are having a new boiler fitted to an existing system, most manufacturers (Worcester Bosch, Vaillant, Baxi) require a power flush as a condition of the warranty. We can power flush before or on the same day as a new boiler installation.

Frequently Asked Questions

What is a power flush?
A power flush is a specialist cleaning process that forces water at high velocity through your central heating system to dislodge and remove sludge, magnetite, limescale, and corrosion debris. The system is then filled with clean inhibitor-treated water.
How long does a power flush take?
Most power flushes take 6-8 hours for an average 10-12 radiator system. Larger systems or those heavily blocked may take a full day.
How much does a power flush cost in London?
Our power flush service starts from £299 for a smaller system and typically ranges to £499 for larger properties. We always provide a fixed-price quote before starting. This includes inhibitor treatment and a magnetic filter installation.
How often should I power flush my heating system?
Most heating engineers recommend power flushing every 5-10 years as a preventative measure. If you are fitting a new boiler to an existing system, most manufacturers require a power flush as a condition of the warranty.
Will a magnetic filter prevent future sludge build-up?
Yes. A magnetic filter (such as Magnaclean) fitted after a power flush will capture iron oxide particles before they accumulate. We install magnetic filters as part of our power flush service.
24/7 EMERGENCIES
0800 123 4567