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  1. Littlespark

    Littlespark New Member

    Hello from the dark side. Electrician here with a little problem.
    2 central heating radiators were added to our house when we had an extension built. The one in the porch is slow to heat up compared with the existing ones in the house.
    By the time the wall stat has cut out as the hall is up to temp, the porch is only hot at the top, cold at the bottom. (It doesn't need bled, done that already)
    Do all the rads now need balanced?.
    The new rads were piped from the back of the bedroom radiator above, not fully back to a manifold, in 10mm(?) hep2o pipework.
    Is there a little trick to balancing? a rule of thumb perhaps?
    Thanks for any advice
  2. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    There's your problem

    Turn your bedroom rad off does the porch one heat up ?

    Can't tee off 10mm
  3. Littlespark

    Littlespark New Member

    ah, hell... Is that the problem?
    I had fully opened the check valve in the porch, which did help in heating the rad from top to bottom, but not as hot as existing rads.
    If I close all the existing check valves half a turn, would it help a little?
    I also notice the TRV is on the return side of the rad. (the TRV's have 2 way arrows on them) This shouldn't matter??
  4. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    I think so

    On the bedroom rad turn the lockshield valve off and see if the other one heats up if it does there's your problem

    Open the porch lockshield valve all the way and slowly 1/4 turn at a time close the bedroom lockshield one eg 1/4 does it heat up after 20 mins etc no keep going etc

    Depends on what type most these days are bi flow
  5. SimonG

    SimonG Trusted Plumber

    Don't tee off 10mm. Back to manifold or 22mm to get a connection.
  6. Littlespark

    Littlespark New Member

    thanks for the advice - ill give it a try.
    I understand now not to tee off 10mm, but its too late now to sort that. I just need to appease my wife now by making the porch heat up more
  7. YorkshireDave

    YorkshireDave Active Member

    Balancing is always a good idea.

    Technically, your are looking to drop 10 degs across rad flow & return.

    open farthest rad LS valve fully.

    Go to 1st rad and turn lockshield valve off. open 1/4 turn let settle till getting approx 10 deg drop. move to next. reduce LS so getting 10. Then go and readjust 1st! Do 3rd then go back to redo 1 & 2. follow pattern till all done.
    When all done set boiler flow to 60 degs
    PIA to do but worth it
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