All you need to know about the costs of power flushing your central heating system including materials, labour and time frames.
This article is all about power flushing a central heating system and part of our series into the costs charged by gas engineers and plumbers. Power flushing is a technique used to clear any sludge from central heating system from the pipes, radiators and heat exchangers. Where sludge collects scale and corrosion surely follow, the symptoms of a central heating system which needs cleaning out include cold spots on radiators that persist even after bleeding, long warm up times, excessive noise and general inefficiency. But once you carry out a power flush you can expect the pipes and radiators to get hotter quicker, with less stress on the boiler and heat be distributed more evenly throughout the home.
Excessive sludge in the system can cause central heating boilers to fail early, the latest efficient condensing boilers in particular are really sensitive so it’s highly recommended to do a full central heating system power flush before installing a new boiler. There is no point in paying for an expensive new boiler that will end up failing early due to excessive sludge, any savings made due to the more modern and efficient boiler will be lost due to the shortened life and replacement cost. In addition, many boiler manufacturers will not honour claims on any new boiler if the system hasn’t been recently power flushed.
Before commencing with the actual job your plumber will start by firing up the boiler and checking the radiators for any cold spots by taking the temperature of each radiator. Then once all the radiator valves are removed or opened and dust sheets placed over carpets and furniture for protection, the power flushing machine can be connected. The first flush is usually a chemical power flush of the entire system which takes around 20 minutes. Afterwards, each individual radiator is then isolated and flushed while a rubber mallet is used to help loosen up any sludge inside.
The second flush again cleans all radiators individually and the fluid is reversed back and forth until the water is clear on all radiators. Usually a final full central heating system flush is then undertaken until the water is free of any sludge. The final step is to add an inhibitor and circulate it through the system, before refitting the radiator valves.
The average cost to power flush your central heating system is typically around £300-£400 with the price depending on a few factors, such as the number of radiators in your house, your location and whether or not you hire a small or large company.
The typical heating engineer will often charge around £150-£200 a day in labour costs. To flush your system it shouldn't take the tradesman any longer than a day but this will depend on the amount of work that's required, so in some cases it can take up to 2 days.
Below are some estimated costs of hiring a tradesmen to power flush a central heating system:
|Number of Radiators||Avg. Cost||Duration|
Individual costs for hiring a tradesman to power flush a system in a semi-detached house with 8 radiators - Total Cost: £400