We highly recommend a powerflush when installing a new boiler, however standalone powerflushes are only necessary in certain circumstances. It is now far more effective and economical to install a magnetic filter.
Why have a powerflush?
If a central heating system is not properly cleansed and flushed when a new boiler is installed then a material called ‘magnetite’ (like rust, commonly referred to as ‘sludge’) builds up over time and circulates around the radiators and pipework. This makes the system inefficient in terms of heat output and can eventually damage the water components of the boiler – a common symptom of this is that you will start to get only lukewarm water.
A powerflush will expel most of the ‘sludge’ from the system, replacing the dirty water with fresh clean water.
Diagnosing a major sludge problem
When sludge is present in central heating water it will leave little piles at the bottom of your radiators. If you feel along the bottom of your radiators and find cold spots then you may well have a sludge problem. It is often accompanied by a noisy, banging system.
If however when you feel along the bottom of your radiators you have one long cold spot then this could be sludge problems, but it could also be circulation problems, so we would first look at other parts of the system to make sure they are working normally before concluding it was sludge. (Cold spots at the top of radiators mean they need bleeding.)
When would we recommend a stand alone powerflush?
If we can diagnose a sludge problem via cold radiators then this is the only time we would recommend a stand alone powerflush, HOWEVER the problem with a powerflush is that it only well suited to old fashioned open vented systems (with a small ‘header’ tank in the loft) where the rust forms as soft brown silt. In a pressurised system the rust forms as a hard, black residue which will not be completely removed by a power flush and pieces of it can often be loosened by the process and re-enter the boiler, days, weeks or months after the power flush has been completed.
So what do I do if I have sludge problems in a pressurised system?
For a pressurised system, the best solution is replacement of the affected parts on the boiler, a chemical cleanse and installation of a magnetic filter to prevent reoccurrence. A magnetic filter device sits on the return pipe to the boiler and removes the black residue from the water so that only clean water passes back to the boiler.
Fitting a magnetic filter is good practice even if you do not have much of a sludge problem, as it will keep your system clean and running efficiently (lowering your fuel bills) and offers long term protection to your boiler.
Prices
We have fixed prices for powerflushes according to the size of your system and can give you a starting price for a chemical cleanse and magnetic filter which will apply in the majority of cases, click here for more details.
If we carry out a powerflush as part of a boiler installation then we discount our prices by 50%. We fit a magnetic filter device as standard on our boiler installations on a parts-only cost basis. Click here to find out more about our excellent heating installations.
