Radiator - how do I turn it on??

Discussion in 'Plumbers' Talk' started by James Lightfoot, Oct 20, 2014.

  1. James Lightfoot

    James Lightfoot New Member


    I have a living room radiator in a new property which is not on, and I have no idea how to turn it on! Every other radiator in the flat has an obvious dial to turn except this one. See attached pictures! It's getting cold, please help!


    James Lightfoot

    Attached Files:

  2. Er, what's on the other end?

    That valve is what's known as a 'lockshield' - it is meant to be adjusted when 'balancing' the whole system, and should then be left alone - all the subsequent control is done using the valve on the other end.

    If the valve on the other end looks the same - no adjusting knob on it - then I suspect that rad will be the 'by-pass' rad which should be on the very end of the rad circuit. These by-pass rads should be left partially 'on' all the time, so that the water still has somewhere to circulate if all the other rads turn themselves off (ie: they have TRVs on them which will shut of each rad as the room they're in reaches the required temp.)

    So, can you tell us please:

    1) what's on the other end of that rad?
    2) what room is it in? (Bathroom?)
    3) what type of valves are on all the other rads?

    Then, if we think we can trust you, we'll tell you how to turn it on (and it has nothing to do with whispering "I love you, radiator...")
  3. James Lightfoot

    James Lightfoot New Member

    Ha ha thanks! The other end is exactly the same, it is in the living room - have attached other end pics of living room rad and other rad valves, thanks for all your help!

    Ps when you say very end of the rad circuit do you mean at the very end of the rad pipes? they are currently boarded in, so i guess i will be unboarding them?

    Attached Files:

  4. sam spade

    sam spade Active Member

    Very few systems need bypass rads nowadays. They were necessary when you had systems which relied on solid fuel, so they could not be controlled accurately, and took a long time to cool down.

    The rad in the lounge has two lockshield valves because it is the one controlled by the wall thermostat, which should be in the lounge.

    The valve with "Honeywell" on the top is a thermostatic radiator valve (TRV). Each number represents a room temperature. You set it to the number which makes you most comfortable (usually between 3 and 4) and the TRV adjusts the rad output to maintain that temperature.
  5. sam spade

    sam spade Active Member

    Just noticed that the rads seem to mounted on a wooden plinth against the wall. Presumably this has been done to hide all the pipework. Unfortunately it means there is a very small gap between the bottom of the rad and the top of the plinth. This will prevent any air circulation through the fins of the rad, so the heat output will be considerably reduced. Rad manufacturers normally recommend a gap of at least 150mm from floor (plinth in your case) to the bottom edge of the rad.
  6. James Lightfoot

    James Lightfoot New Member

    THanks, have attached a picture of the thermostat in the lounge. (See attached) I have set it to max but still there is no heat from the lounge radiator, also the red light flashes for a second then turns off - normal?


    Attached Files:

  7. (Soz - had to pop out. Sam has filled in most of the necessary :) )

    The large 'wheeled' knob is a TRV - a thermostatic rad valve. That is meant to keep your room at the temp you want, as set on that control.

    Your first rad doesn't have one of these for some reason. Is there a wall-mounted room stat in your living room, or anywhere else in your house? (Update - you've told us!)

    Ok, that rad; you have two 'identical' valve ends, so one we'll make the lockshield which will be 'set and forget', and the other we'll use to turn the rad on.

    How to tell which is which? Doesn't really matter, but it's best 'convention' if the lockshield is on the 'return'. Your other rad - the one with the TRV has the TRV on the RH side - so that is usually the 'flow' (the water input to the rad) so let's call the RH valve on the other rad the 'flow' as well :).

    This is what to try: get a wee spanner that'll fit that square spindle. Ok, first go to the LH valve and try closing it (turning it clockwise) but note where you are starting from so's you can return there afterwards. I'm guessing - if that is the lockshield - you'll be able to turn it, ooh, a half turn, or 3/4 turn or similar and it'll then stop (fully closed).

    If that is what indeed happens, then open it again the same amount, leave it alone, point to it and say "You are the lockshield, my child". (But don't say that out aloud in case someone's watching).

    Then go to the RH side where I bet you'll find that this one is already fully shut off - you cannot turn it clockwise at all.
    That one is therefore the controlling valve (you know what to do - point at it and ...)

    Ok, if I got that a* over t*, then let me know if it's the exact opposite - the RH one has the best part of a turn in it before closing, and the other is already closed... :rolleyes:

    Anyways, the good news is that if you open (anti-clockwise) the 'closed' one, the rad should come on. Only 'open' it 2 or 3 full turns - it'll be pretty much full on by then.

    Now, you say your sitting room has 2 rads, and one has a TRV on it? Well, that one doesn't need the TRV and shouldn't have it - so open it FULLY and leave it. You then control the room temp (and the rest of the house) by using your room stat.

    (I don't know if it should 'blink' like that, but it doesn't really matter - if the other rad comes on when you turn it up, then it's working...)

    These 2 rads in the living room - does ONE currently come on? (The one with the TRV)?
  8. Is this going to be your own home? If so, are you planning to 'bury' these pipes? That boxing looks hellish, and will also reduce the rad's effectiveness as Sam says.
  9. sam spade

    sam spade Active Member

    You have a wireless thermostat. The part in the lounge is battery operated and the flashing light can mean the batteries need replacing. Press in the catch, near "Honeywell", remove cover. This will give access to the batteries. Only use Duracell. Do NOT use rechargeable batteries.

    Link to thermostat instructions:

  10. James Lightfoot

    James Lightfoot New Member

    Thanks everyone, Devil, quick Q, see attached, which part should i be trying to turn?

    Attached Files:

    • turn.jpg
      File size:
      106.8 KB
  11. DIYDave.

    DIYDave. Screwfix Select

    With the heating on and the other rads hot, is the pipe leading to this cold rad hot ?

    Hopefully the pipe is hot which probably means this rad has been shut down and just requires a few turns of the flow valve, as above (also possible balancing)

    If the pipework is cold to the rad,it probably indicates a blockage \ airlock somewhere leading to the rad

    Good luck, as you say its getting cold !
  12. Shoorly if the rad is fully shut off, then the pipes leading to it will be cool too - 'cos there's no flow...?
  13. Rulland

    Rulland Screwfix Select

  14. James Lightfoot

    James Lightfoot New Member

    Thanks guys, going to the DIY shop and buying a spanner to try and get radiator working, wish me luck...

    ps that boxing is hellish, will be getting rid of
  15. James Lightfoot

    James Lightfoot New Member

    ok so i couldn't turn the RHV at all, but could turn the LHV, I have twisted it a bit ACW until a dribble of water came out, then twisted it back till the dribble stopped. Still no heat though...
  16. Wha...?!

    Where did the 'dribble of water' come from?!

    You are turning that small squared-off tip of the thin brass vertical spindle, aren't you?

    And the RH one has to bludy turn as well - they can't be that stuck... :rolleyes:
  17. James Lightfoot

    James Lightfoot New Member

    it appeared at the base of the nozel.... and yes, the other one is PROPER stuck. I think it's time to call a professional.... but thanks everyone! I have learnt a lot! I will be back (after all i have just bought a my first flat and want that DIY king badge)
  18. "the base of the nozzle" - where that brass shaft disappears into the main body of the valve? In which case the gland seal is shot and that is quite likely why that was shut down - to prevent that dripping.

    Yep - time to get the pros :).

    It isn't a complex job as such, but there are a few things you need to be aware of, so best to watch someone else do it first. But don't stare too hard - really annoys tradespeeps.

    (Polite to actually ask if they mind you watching - tell them you are fascinated by it as you know nuffink...)
  19. James Lightfoot

    James Lightfoot New Member

    Thanks, will let you low what they say!

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