broken radiator valve

Discussion in 'Homes and gardens' started by josephiney, Mar 10, 2008.

  1. josephiney

    josephiney Guest

    I'm looking foradvice on how big a job it is to replace a broken radiator valve.

    I've just moved into a new house and one radiator wasn't working. I thought it just wasn't turned on fully and was a bit stiff, so I used an adjustable wrench to open it (the right hand side valve), but before I'd applied any pressure the valve pin just snapped off.

    Before I call a plumber I want to get an idea of how big a job this will be?
    Is it common?
     
  2. oopsbuddy

    oopsbuddy Frequent Poster

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    It's not a big job, and cheap to fix if you know how to do basic DIY. If you don't, you may have to pay someone to do it for you (see previous posts on plumbing!). A good hardware shop/builders' suppliers will sell you the new valve and any other fittings you need, and will probably even tell you how to replace it if you ask. Basically, turn off water, disconnect rad from valve and drain rad, undo connection at bottom of valve (to supply pipe), remove old valve and reverse this process to fit new valve, remembering to use enough PTFE tape on threaded joints (start winding tape in same direction as the tightened nut so that when nut starts to join the thread, it travels in the same direction as the outermost layer of tape, instead of against it which will start to unravel it), tighten, turn on water, open new valve and refill radiator (loosen bleed cap at top of rad until rad full). That should do it! Good luck.
     
  3. DavyJones

    DavyJones Frequent Poster

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    oopsbuddy, you make it sound so easy! It can be tricky and it will take longer to drain down heating system and refill it getting all air locks out than it will take to change valve. It would take a pro between two and four hours. It can be done by a DIY-er if your confident enough, i would recommend tying up ballcock on small tank in attic, (this feeds your system if it's of the vented type) you will probably find a drain off cock at boiler or on a leg of a rad, stick a hose on it and open. be sure and open vents on all rads so that all water is drained (less chance of airlock when refilling) but remember to close before refilling. change the valve and untie ballcock, turn off drain off cock and vent all rads in turn. your biggest potential problem will be an airlock after you refill system. every plumber here will have spent wasted hours trying to free air locks on systems.
     
  4. josephiney

    josephiney Guest

    Thanks for the advice but I think its sounds like a job for a professional. If I'm an idiot enough to break it in the first place, I think I need someone more competent to fix it. Cheers.
     
  5. Gordanus

    Gordanus Frequent Poster

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    Plumber did it for me for 50 cash, including the new valve. It was an upstairs radiator. He said if it was downstairs he would have had to drain the whole system....much more expensive
     
  6. Pope John 11

    Pope John 11 Frequent Poster

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    Is this true....I have a problem with the valve to an upstairs radiator.

    Is it as simple as doing the following:

    1. Lift up the ball-cock
    2. Turn off the water - (Is this the water at the mains coming into the house)
    3. Open the valve & drain the radiator.
    4. Remove the valve.
    5. Replace the valve.

    Is this correct or do I have to do something witht he other radiators.

    Can someone please put this into a 1,2,3...order.

    Appreciate it
     
  7. DavyJones

    DavyJones Frequent Poster

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    1 tie up ballcock in small tank. This will prevent tank refilling heating system.
    No need to shut of mains. do one or the other.

    2 drain system from a pt lower than you intend to work. you may have a DOC(drain off cock) at boiler or fitted to downstairs rad. looks like a little tap where you can attach a hose. There will be one at the cylinder. This is not the one you want

    open vents in all upstairs rads to allow draining to happen at a quicker speed. Once you feel that the top half of system is empty, open valve slowly, if you still have water, drain off some more.

    besure and close vents when you refill, once system is refilling, vent rads, check work for leaks, turn on boiler. heat to all rads, job done.

    Good Luck.
     
  8. Pope John 11

    Pope John 11 Frequent Poster

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    If I do not have a drain off cock on a radiator down stairs, where else is it likely to be in the house.
     
  9. DavyJones

    DavyJones Frequent Poster

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  10. Pope John 11

    Pope John 11 Frequent Poster

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    Cheers for that Davyjones.

    I will stay away from the hot press where the hot water cylinder is.

    I will look this evening.

    The gas boiler is in an external outhouse to the back of the house.
     
  11. Pope John 11

    Pope John 11 Frequent Poster

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    Sorry guys, I couldn't find the drain cock valve....are there any other forms or types of valves that I should be looking out for to drain the system.

    Is it possible to drain the system by bleeding the radiators down stairs with the upstair radiators bleeding points open.
     
  12. Pope John 11

    Pope John 11 Frequent Poster

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    Will the system fill automatically when you release the ballcock in the attic, & at what point should you open the vents to airlock the system?

    Should you open the vents to all radiators, upstairs & downstairs?
     
  13. DavyJones

    DavyJones Frequent Poster

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    yes, system will fill as soon as you reinstate water supply.

    Give it a few minutes and start venting.

    you only want to drain about half of the system, so you should already have water in downstairs rads.

    Once system is filled and if some rads are cold you may have to turn off rads that are hot to free out any remaining air locks.
     
  14. Pope John 11

    Pope John 11 Frequent Poster

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    Perhaps you can confirm if the above is possible
     
  15. DavyJones

    DavyJones Frequent Poster

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    It is possible but it would take forever and a day. Here are two options.

    1 find a small rad near a door. Close both valves off, rip valve at rad and drain into basin bucket, once emptied, remove rad. either attach hose to rad valve and drain down or open valve and drain into bucket.

    2 Maybe the easiest thing to do is buy a frezzing kit, they are inexpensive. they come with an aerosol can and sleeve, follow instructions.
    Go to problem rad, turn off the valve that is ok, place frezzing sleeve over pipe that has faulty valve and form an ice plug. then drain rad and swap valve. the ice plug will be good for 30 mins.

    Good thing with option 1 is you can fit a DOC once it is done. Good thing about option 2 is that you don't have to drain down system and have to deal with airlocks. It's quicker too.
     
  16. Pope John 11

    Pope John 11 Frequent Poster

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    Cheers for that Davyjones.

    Can anyone tell me where is the best place to buy TRV. I checked them in B&Q & they cost €30 each...however they had none in stock yesterday. I thought that was expensive.

    Any other thoughts welcome
     
  17. DavyJones

    DavyJones Frequent Poster

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    Any plumbing merchants. Chadwicks, heat merchants etc. Expect to pay €14-ish for a TRV pack. 1 TRV and 1 lock shield vavle.
     
  18. Pope John 11

    Pope John 11 Frequent Poster

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    DavyJ do you know any place that would be open today. I am based near city centre/Drumcondra
     
  19. DavyJones

    DavyJones Frequent Poster

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    Don't know your area, it would be worth trying Wicks and other DIY stores. All plumbing places will be closed today.
     
  20. DGOBS

    DGOBS Frequent Poster

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    Davy is right guys, stay away from draining and refilling systems yourself, even the professionals run into problems doing it.

    If there is enough pipe between the wall/floor and the rad valve, you could always hire an electric pipe freezer (I don't recommend the spray ones) clamp on either side, wait a half hour to freeze, then drain just the rad change the valve wait to thaw and your done. Easy peasey