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What is a Chemical Flush?

Rust, sludge and debris can build up in your boiler, pipes and radiators over time and prevent hot water from flowing efficiently around your central heating system. A chemical flush can break down the sludge clogging your system to help hot water flow more easily and ensure your system operates at its best. 

Read on to discover everything you need to know about chemical flushing, including the benefits, how often you should get one, and what it costs. 

Why should I get a chemical flush?

When your central heating system develops a build-up of debris, it can affect the energy efficiency of your system and prevent hot water from travelling around your home. The build-up of accumulated materials can lead to cold patches on your radiators, parts of your system not heating correctly and strange noises coming from your boiler. 

If any of the above issues sound familiar, a chemical flush could be what you need to solve the problem. A chemical flush is designed to deep clean your system and remove rust and debris from your boiler, pipes and radiators.  

The benefits of a chemical flush

Cleaning out the build-up of debris inside your central heating system has many benefits, such as:

  • Increase the lifespan of your boiler
  • Boost the effectiveness of your heating system
  • Improve the energy efficiency of your heating
  • Protect your system from rust and debris
  • Save energy and money in the long term

How often should I get a chemical flush?

Your engineer will likely carry out a chemical flush after installing a new boiler, radiator or pipe system in your home. Once installed, you may need to get a chemical flush now and then to rid your system of dirt and debris. 

Most boilers only require a chemical flush a few times throughout their life, and how often you should get one will depend on your boiler. The tell-tale sign that your system might need a chemical flush is your radiators are cold at the bottom when your heating is on. 

How much does a chemical flush cost?

The cost of a chemical flush can vary, depending on the age and size of your central heating system and the company you choose to carry out the work. Chemical flush prices range between £300 and £700 on average, but you may end up paying more if the job is complex. Also, keep in mind that your engineer may spot other underlying problems that need fixing when performing a chemical flush, which will increase the cost. 

How long will a chemical flush take to complete?

It depends on the size of your central heating system and how much debris needs removing. A chemical flush usually only takes a few hours, so not too long. When your engineer completes the job, they will check your system is working as it should, and you will notice the improvements and feel the benefits within as little as a couple of hours. 

What is the difference between a chemical flush and a power flush?

A chemical flush is a more basic cleanse than a power flush, which uses high pressure to push a mixture of chemicals through your boiler, pipes and radiators to dislodge sludge and debris. 

Unlike a power flush, a chemical flush uses gravity to flush a blend of chemicals into your system, leaving the chemicals to circulate and break down the debris. After this process, clean water is flushed through the system to remove the loose debris and sludge. 

What is the difference between a chemical flush and a Magnacleanse?

A Magnacleanse will give your central heating system a thorough clean and remove stubborn, unwanted debris and magnetite that have built up over time. Your engineer will put a magnetised agitator inside each radiator to attract the sludge and debris, which they will remove and dispose of once your system is clean. 

Your engineer may also recommend installing a magnetic filter on your system to provide ongoing protection for your boiler and radiators.

Who should perform a chemical flush?

You should hire a Gas Safe registered engineer to carry out a chemical flush. Attempting to perform one yourself could lead to damage or further problems and invalidate your boiler warranty. Besides, a chemical flush is a messy job best left to a professional. 

While the thought of spending between £300 and £700 to get a qualified engineer to perform a chemical flush may not please you, it is a job worth doing because it will improve the energy efficiency of your system and help to reduce your heating bills.