Unvented Hot Water Cylinder Certification

Discussion in 'Plumbers' Talk' started by Tharrison, Aug 2, 2016.

  1. Tharrison

    Tharrison New Member

    I am due to have an unvented hot water cylinder fitted in my property to replace the old vented cylinder. I have two questions:

    Does the Heating Engineer need to have a certification to do this, or be registered with anyone ?

    Do I need to inform building control ?

    I have been searching online for hours and can't find a definite answer so hoping you guys can help !

    Thanks in advance !
  2. PLPlanning

    PLPlanning New Member

    Yes the installer should to be certified to install an unvented cylinder. These cylinders if not installed correctly are bad news. Although there hasn't been any failures (to my knowledge) in this country. They can explode.
    Water under pressure boils at a higher temperature than 100 degrees c. So in theory if there is a fault in the system and too much pressure is built up, any rupture in the cylinder would mean that the water Could flash to steam. This is an explosion.
    Make sure the installer has undertaken a unvented cylinder training course. You don't need to notify building control as the installer takes the responsibility and fills out the installers part on the documentation along with his registration number.
    If you have any doubts, ring the local building control and they will clear up any queries that you have.
    Having said all this, these systems are brilliant. Equal hot and cold water pressure all over the house.
    Great for showers. Good kit.
    KIAB likes this.
  3. Charles horder

    Charles horder New Member

    Is there an actual certificate a plumber has to show you he is a qualified unvented cylinder installer. Having left messages with 7 companies so far and 3 visits from plumbers all giving me different remedies and finally settling on a company who seem qualified to do the job, I am having a problem with this certification. They said they can sign off the job and give me a guarantee and their registration number, but is that enough. I look forward to some qualified advise please. Thank
  4. KIAB

    KIAB Super Member

    He should have a G3 certificate to service & install unvented cylinders.
    Heat likes this.
  5. Heat

    Heat Screwfix Select

    The cylinder has to have a certificate for building control.
    Plumber has to be G3 qualified and will need to put his qualification number on the certificate.
    I am G3 qualified, but I have only the paper certificate to prove it. Some plumbers will have a card, or it could be part of their gas qualifications.
    Edit, - forgot to say you will have no cylinder warranty (usually 25yrs) if you have an illegal install, or if you don’t get unit serviced every year and have service record.
    It is the law to be G3 qualified on unvented, given the risk of explosion if not installed properly
    KIAB likes this.
  6. Charles horder

    Charles horder New Member

    If they don’t have a G3 cert but have a BPEC registration or Gas safe registration does this also qualify as installer of unvented cylinder and therefore making it legal
  7. andy48

    andy48 Screwfix Select

    Whoever they have certification from, the certificate (which may be a plastic card) must state that they are certified to install unvented hot water systems, and the qualification must be in date.
    Heat likes this.
  8. Heat

    Heat Screwfix Select

    The gas qualification needs to also have G3

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