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Which outside tap and how to replace?

Discussion in 'Plumbing and Central Heating' started by DIYNotIan, 11 Feb 2019.

  1. DIYNotIan

    DIYNotIan

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    Hi

    My outside tap broke the other day. At least I think it did - it just started running water by itself and wouldn't turn off. So we've had the water off at the main stop cock since.

    I'd usually just call in a plumber but no one can come quickly and I want to start doing more of these things myself anyway.

    So firstly can anyone recommend what I should get? Are the cheap ones at screwfix any good (they get good reviews)? If so, what's the difference between these:

    https://www.screwfix.com/p/outside-tap-with-double-check-valve-15mm-x/37241

    https://www.screwfix.com/p/outside-tap-with-hose-union-15mm-x/41948

    What's a double check valve?

    Or would I be better off with a lever tap (less to go wrong?):

    https://www.screwfix.com/p/pegler-pb50-hose-union-bibtap-15mm-x/6263v

    Happy to spend more if it's worth it though.

    Do I need to buy anything else?

    In terms of how to replace it, I'll look it up once I've got the tap, but any words of wisdom in the meantime would be much appreciated.

    Many thanks
     
  2. bernardgreen

    bernardgreen

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    It prevents water going backward through the tap. This protects your drinking water from being contaminated by water from a hose pipe getting back into the house
     
  3. DIYNotIan

    DIYNotIan

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    Well that sounds like a good idea! Seems only the first link from screwfix has a double check valve so I'm guessing that would be the best one to get, especially as the tap is a feed from the pipe running to the kitchen sink...
     
  4. oldbuffer

    oldbuffer

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    1. The water regulations state that the double check valve should be inside the property.
    2. The type of outside tap with a built in check valve:
    2a. Should only be used to replace a tap of the same sort, i.e. one with a built in check valve.
    2b. The check valves are quite susceptible to damage from freezing.
    3. If you want to do the job properly:
    3a. Install a double check valve and drain off point inside the property.
    3b. Install either the ordinary (no check valve) or lever valve outside. It is more difficult to get a partial flow with the lever type, but if you want water only on or off, it would be OK.
    4. If you aren't bothered about complying with the water regulations, or you existing tap has a check valve built in, install the one with the double check valve.
     
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  5. DIYNotIan

    DIYNotIan

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    Thanks oldbuffer. Well, I'd prefer to have it done properly so maybe I should wait for a plumber. Hopefully they would do it in compliance with the things you mention and regs.

    I've no idea whether the current tap has a check valve fit in. Can you tell by looking?

    I think it would be a good idea to have a stop valve inside the property so that I can shut the tap off in winter. Is that a good way of preventing issues with freezing?

    We have another outside tap coming from the WC. As it isn't so close to the kitchen is a double check valve less important? Or would there be one in all outside taps running from the mains?

    Thanks again
     
  6. Hot&Cold

    Hot&Cold

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  7. oldbuffer

    oldbuffer

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    1. If the current tap has a small hexagon headed or screwdriver slotted nut, which seems to serve no purpose, on it, it probably has a check valve.
    2. The best way to run it is water in : check valve : isolation valve : tee off to pipe through wall and outside tap : drain off valve. This enables you to isolate the outside tap in winter. Then, by isolating it, opening the outside tap and opening the drain off point minimises the amount of water which can freeze. If you can arrange the pie to come out of the wall, descend vertically for a little and then fit the tap. this enable all the water to be drained. If fitting an isolating valve, fit a full bore quarter turn valve to avoid restricting the flow.
    3. There should be a double check valve on all outside taps.
     
  8. Gasguru

    Gasguru

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  9. DIYNotIan

    DIYNotIan

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    Ok, great. Thanks for all of that. I'll take a look when I'm back home and see what's what. I'll take a photo of I cannot figure it out.

    What would a double check valve on the inside pipe look like? Just so I can see if there is one already...

    Thanks again
     
  10. Ian H

    Ian H

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    Ours did the same, the washer had split. They gave me one for free at the plumbers merchant and it took 2 minutes and an adjustable spanner to fix it.
     
  11. Gasguru

    Gasguru

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  12. DIYNotIan

    DIYNotIan

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    I did think washer when it happened. But I couldn't get the tap undone to check. It's pretty much seized and no longer attached to the wall either which didn't help.

    Any tips? And I'm a novice, so even an idea of where it needs to be undone and which washer would be great

    We'll be having the kitchen redone soon which will include plumbing, so maybe getting it up to standard should be done then and for now I should just fix it as cheaply as possible so we can turn the mains back on!

    Thanks for the many helpful replies. Really appreciate it.
     
  13. Gasguru

    Gasguru

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    Post a pic but it might be easier if you just replace the whole stopcock for now.
     
  14. Ian H

    Ian H

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    I’d go for a direct replacement if I were you, then have a think about an upgrade when your kitchens done.

    I put a load of ptfe tape on, maybe 15 wraps, then screwed the tap back into the socket in the wall.
     
  15. bobasd

    bobasd

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    without seein it we dont now how its fixed?
    if the tap is threaded into a fitting then just unwind it an replace with like for like.
    even cheaper would be to use a thread-in plug or a cap on any remaining stub of cu tube.
     
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