South Thames Gas offers a Power Flushing service – a standard term used for cleansing central heating of sludge with the aid of chemicals.

Rust occurs in central heating systems which produces black sludge and lime scale build up. Such blockages result in cold radiators, no hot water, boiler cutting out an irritation boiler noises.

Power flushing remedies these problems, protects against rust and makes central heating efficient and economical.


The cleaning and treating of central heating systems

All new systems should be pre-commission cleansed in accordance with BS:7593 and Benchmark. This ensures flux residues, excess jointing compounds, mineral oil and other contaminants that can be found in the system following installation, and that can effect the performance of the system or cause component failure, are removed. It is important when installing new boilers into old systems that all sludge is first removed from the system or this could accumulate in the new boiler and lead to premature failure. Additionally, in hard water areas existing systems will have accumulated lime scale together with corrosion deposits in the heat exchanger, which could easily have reduced the boiler efficiency by over 5%

Extend the life of your heating system and solve problems for sludge build up in radiators, noisy boilers, pumps, leaking soldered joints, cold water storage situated in the loft and hot water cylinder lime scale deposits, with cleansers, inhibitors and protectors designed to remedy all type of problems, prevent corrosion and restore the systems efficiency.

Fuel wastage

Without treatment, corrosion debris will accumulate in the boiler causing increasing lime scale deposits, reduced heat transfer and up to a third of a fuel bill going to complete waste.

Frequent venting

When the top of a radiator is cold during operation, either air or hydrogen is to blame. Hydrogen gas builds up as a by-product of electrolytic corrosion and is flammable (due caution is required).

Pump seizure and failure

The abrasive and magnetic properties of black oxide sludge increase shaft and bearing wear in pumps causing them to stick or fail.

The solution

Pre-commission cleanse new systems and thoroughly cleanse existing systems with Fernox Restorer or Fernox Super concentrate System Cleaner before adding a suitable Fernox Protector to maintain efficiency and ensure the longevity of the system.

Call our Gas Safe engineers on:

FREEPHONE: 0800 0 74 76 78


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0800 0 74 76 78


0207 326 5239

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South Thames Gas
62 Railton Road
Herne Hill
SE24 0LF


Denmark Road, SE25 5QU
Landor Road, SW9 9RT
George Lane, SE13

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"Quality is our aim, its sure to be your gain"

for all your central heating, gas & boiler needs

Call our Gas Safe engineers on:

Freephone: 0800 0 74 76 78

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