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Discuss Air and Micro Bubbles in the Central Heating Forum area at

  1. digi77

    digi77 New Member

    Have a new (6 mth old) ideal vogue system boiler doing heating and unvented water tank (megaflow) via 2 port valves, all rads have electronic trv's and a bypass fitted before the 2 ports (rads and a lot of pipework was new 3yr ago system was cleaned when new boiler fitted). Under normal heating system is quiet (weather comp) when hot water tank calls flow temp increases boiler max 80 (ignores weather comp) still quiet but when satisfied and 2 port closes I get a rush of air into the nearest open rad, if I bleed the rad little or noting there. Fitted a spiro vent on the flow from boiler about 4ft away have had a little out of it but not much. System has held pressure for months.

    Have 2 auto air vents on the system should these be open or closed, I believe there is also one in the boiler should this be open or closed. Saying that the spiro vent is also a type of auto vent and that's designed to be open all the time.
  2. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Sounds like Bypass noise not air just water movement
    • Agree Agree x 3
    • Like Like x 1
  3. Rob Foster

    Rob Foster Top Contributor!!

    Schwepps tonic has micro bubbles in it oh yeh , no such thing at
    ambient temp and normal atmospheric pressure... air,co2 whatever are a constant volume
    look ekeswhere than micro bubbles. centralheatking
    • Like Like x 1
  4. digi77

    digi77 New Member

    The air/bubbles occur after hot water tank been on ie between 70-80deg flow. System is at just over 1 Bar cold just under 1.8 bar hot and heating on.
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