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    Boilers Hot Water Plate Heat Exchanger?
  • Plate Heat Exchanger

    What is a Plate Heat Exchanger

    This system uses metal plates in an enclosed space to generate heat.

    Because they don’t take up much room.

    Plate heat exchangers are increasingly common in domestic applications.

    Both in their own right or as a component in another system such as combination boilers.

    So How do plate heat exchangers work?

    Typically, a coiled pipe containing one fluid will pass through a chamber containing another. 

    Walls of the pipe will be made from either metal or another highly conductive material. 

    Heat is transferred to metal plates which have a very large surface area for their size.

    What are the pros and cons of Plate heat exchangers?


    Heat Transfer for the size is quite efficient.

    These are available in numerous sizes.


    Requires hot water to enable it to work.

    Larger the Plate Heat Exchanger, the more maintenance it needs.

    They are more at risk to scale build up.

    Larger heat exchangers have gaskets which can fail.

    Combination Boilers

    Most combination boilers fitted in the united kingdom have a hot water plate heat exchanger fitted.

    Give that instant hot water when you turn the tap on. 

    Overtime the most common fault that happens is lack of hot water. 

    You may find that the water runs hot and then warm.

    But lack that totally hot water. 

    Is very annoying when trying to shower.

    The Cause

    When your boiler is installed.

    Manufacturers recommend that the whole heating system be flushed out with a cleaning agent.

    To remove any fluxes and debris that may be present within the system. 

    Once flushed, an inhibitor should be added to the system.

    This will protect the system from scale and sludge build up. 

    Ok, your system is protected, so why do i still have sludge within the system?

    There are many reasons.

    One being that the system was not fully flushed out when the boiler was fitted.

    Another being if you have removed any radiators for decorating.

    When you refit them the inhibitor has to be topped up.

    Because when you add the water back in to the radiators the inhibitor is diluted down.

    The Annual Boiler Service

    When you have your annual boiler service carried out.

    The engineer should also check the quality of the water within the system.

    This will tell him if the inhibitor needs topping up, which most of the time it does. 

    Something that seems to get missed out on the service. 

    It’s quite easy to do, you take a sample of water into a little tube.

    Add a tablet that changes colour, this will tell you the volume of inhibitor within the system.

    Inline Filter MagnaClean

    Another recommendation from the boiler manufactures.

    Is that an inline filter be fitted to the return pipe of the boiler. 

    This will stop 99% of any sludge and debris.

    Entering the boiler and causing damage to both heat exchanges.

    If you have a combination boiler fitted within your property.

    And you are having problems with the hot water getting hot then colder.

    There’s a good chance the hot water plate heat exchanger is partly blocked. 

     No cure, it’s a new heat exchanger, in some cases it could be a new boiler.

    Clean Water Within Your heating System.

    Having clean water within your central heating system is very important. 

    When your boiler was fitted, if the system was cleaned and an inhibitor added.

    You should have clean water, if not then you may need to have your system flushed out.

    If you are having problems with your hot water.

    And would like to talk on how to resolve this issue.

    Lets us know, and we can send an engineer out to see what needs to be done.