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Discuss Radiator not heating up as quickly as others? in the Central Heating Forum area at

  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
  8. Littlespark

    Littlespark New Member

    valve.jpg (hope you can see the photo)
    This is the check valve on the bedroom rad... It wont move at all trying to turn the flattened shaft at the top.
    On a separate question.. how do I drain the system using the drain cock on the side without it pouring all over the carpet? Theres a square valve inside the drain. how do I unscrew that, if theres a hose connected to the outlet?
  9. Dkdc71

    Dkdc71 Member

    Is there a valve on the opposite end ,I hate and dread those micro bore systems havent seen one in years or know any plumber that fits them now as far as I remember that is not a drain off it was a return someone here will recognise that valve more good luck
  10. Harvest Fields

    Harvest Fields Trusted Plumber GSR Top Contributor!!

    Get an adjustable spanner on the spindle sticking up in the air. Clockwise is off/closed and anti clockwise is on/open. It is called a drain off lockshield valve. If you turn that valve off and the valve/thermostatic radiator valve on the other end off, then put a small tray/bowl underneath and remove the square screw from the drain off part with a radiator bleed/vent key (a little water will come out so do it slowly so that you know the valves are holding) then attach a hose pipe to the valve and to a drain outside. Open both valves back up and the water will drain from the system if the drain is downstairs.
  11. Littlespark

    Littlespark New Member

    The other end of the radiator has the TRV fitted. This looks like a drain off, having the push on hose type fitting there. Every rad has the same thing, upstairs or downstairs. I guess the spindle is just seized. I'll try again with a little more effort.
    It makes sense now. Closing the valve will drop it below the level of the drain, allowing me to remove the plug from inside the drain. Opening the valve up will then let the water out.
    Personally, I like the pipes coming out the wall behind the rad, rather than straight up from below the floor. But it could have been neater.
  12. Dkdc71

    Dkdc71 Member

    We dont use that type valve here but best of luck with it let us know how you get on
  13. Littlespark

    Littlespark New Member

    yeh.. I don't know why they have a drain valve on every rad... should just be one at the lowest point in the system??
    My house was built as part of a larger development. They somehow changed manufacturer of the TRV's half way through my house.
    Also changed design of my doors half way through as well.
    I have a unique house on the street. ;)
    • Like Like x 1
  14. Best

    Best Trusted Plumber

    Those valves should be used only on low points, - like on drop fed radiators.
    I never use them because it ain't hard for me to drain a rad
    • Like Like x 1
  15. Dkdc71

    Dkdc71 Member

    Those valves should be at the bottom alright ..bottom of the scrap bin wouldn't use them or microbore pipe
    • Agree Agree x 1
  16. Best

    Best Trusted Plumber

    Same with me, - never liked cheap valves, or microbore and never installed either, except to replace parts of systems. Always thought of both years ago as for cowboys, tbh.
    To be fair, the plastic Microbore is probably better than copper Microbore in some ways as it is more flexible. But Microbore can't have long runs and plastic Microbore will be worse as it has smaller internal bore due to heavier walls on plastic pipe, plus supports at each joint making it even smaller diameter at those points.
  17. Chuck

    Chuck Active Member

    This sort of puzzle often has an answer that starts "What I actually told the appentice to do was..."
    • Like Like x 2
    • Funny Funny x 1
  18. Dkdc71

    Dkdc71 Member

    If I told an apprentice to use that if he didn't sack me I would sack myself it's great seen a system with good pipework and piped properly when I see that stuff it would bring a tear to a glass eye .we use to say you wouldn't put a honda 50 engine on a ducati so why try
    • Agree Agree x 1
  19. king of pipes

    king of pipes Trusted Plumber GSR

    Nothing wrong with a manifolded system if used in the right application it has to be designed and fitted properly though , it allows a heating system to be piped with very few or no fittings under the floors thus eliminating possible leak issues , i recently did a electric boiler and each rad had deadicated 10mm supplies from 22mm flow and return manifolds and it worked out perfectly, drain points should always be fitted to all low points on the system to aid draining and flushing of the system, thats my take on it but i am sure others will have their own opions. Cheers kop
  20. Dkdc71

    Dkdc71 Member

    They were a diy heating system over here in the early 80,s a lot of chancers where fitting them when we came across them we removed/replaced they were the worst system ever used over here constantly blocking up any system we came across the people would say worked great for the first year and then one or more rads would start blocking
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