Hot Water Shutoff Valve (under bath sink)

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by CdnFlyer, Jun 26, 2012.

  1. CdnFlyer

    CdnFlyer New Member

    Hi all...
    I have a leaky hot water valve under the bath sink. Single storey slab home. The only water shut-offs I have access to are at the street and on the hotwater tank. when i shut off the valve at the tank (electr off first) I still have enough pressure at the valve to spray water if I try to loosen it. Do I need to drain the HWT and open all taps to stop the water flow? Or is there an easier way? If draining the tank is the answer, how do I do it so that I don't lose pressure or get air into the lines??
  2. Gary Swart

    Gary Swart In the Trades

    Yakima WA
    Never can understand what people will plumb a house without the ability to shut the water off in case of an emergency! Fortunately, this particular problem can be dealt with fairly easily without taking drastic measures. Shut the valve on the water heater off. The only pressure in the pipe can be easily relieved by just opening a hot water faucet. However, unless that faucet is below the level of the problem valve, there will still be water in the pipe. It will not be under pressure, but will drain when you remove the bad valve so you'll need a couple of pans to catch that water to avoid a mess. The best replacement valve is a 1/4 turn rather than one that requires several turns to shut off. Valve for sinks and toilets should be full on or full off, so no point in the mega turn style. I would suggest you explore the installation of a master shutoff valve on the main supply line at or very near the entry point to the house. If someday you have a broken pipe and your house is being flooded, you will praise the day you spent the $$ for it. Yes, it will probably require a plumber, but you never know when that break might happen. I could tell a story about how I learned this lesson, but suffice it to say, I've been there!
  3. Terry

    Terry Administrator Staff Member

    Bothell, Washington
    Like Gary mentioned above, even with the water shutoff, you will need a pan to catch water if it's the lowest point.
    Opening other faucets will allow the system to drain down sooner. And air? When you move the water, it's replaced by air. No big deal, when the water gets turned on and you open the faucets the air will be purged.

    If the water heater siphons, you can loosen the connectors to the top of the tank to break the siphon. Do not "remove" the connectors unless you are planning on replacing them. My rule of thumb is that you always replace them once they are removed.

    We like to use 1/4 turn valves.
    Last edited: Jun 26, 2012
  4. mikeplummer

    mikeplummer Plumber

    Ontario, Canada
    1/4 turn stops are nice, but not feild repairable, for this reason i always use mulit turns...i.e. brasscraft r19 (angle) or r14 (straight)
  5. Gary Swart

    Gary Swart In the Trades

    Yakima WA
    Gosh Mike, I'm 77 years old and never ever have had to repair a shut off valve. Replace some when remodeling, but never have had one go bad. Maybe I just lucky, but if I do have one start to leak tomorrow, I don't think I'll bother trying to repair it. They're too cheap to mess with IMHO. 'course, I'm not a pro, but even then I think I just as soon make my $$ on the mark up on a new valve than on the labor to repair one.
  6. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    New England
    They're usually fine, but the multi-turn ones can start to leak if all the packing has dried out after umpteen years. Often, all it needs is to tighten the packing nut slightly. But, if it does not shut off, the seat or the washer may be shot. On ball valves, especially those with a plastic stem, it can shatter if it's really old and you may have stored some cleaning chemicals underneath the sink. That can affect things, both plastics and metals depending on what's there.
  7. hj

    hj Moderator & Master Plumber Staff Member

    Cave Creek, Arizona
    quote; 1/4 turn stops are nice, but not feild repairable

    I have found FEW stops which were worthy of my time to "repair" them. Those that I did, I just removed the mechanism from a new valve and screwed it into the old one. Normally the 'repair" is to take it off, and throw it into the scrap bin before installing a new valve. Turn the heater valve off as much as possible without breaking it. Then lift the lever on the safety valve and prop it open. Any water leaking through the valve will drain out of the discharge pipe before it can get into the piping and give you a problem. IF the valve does not open, or leaks afterwards, that is a sign that it should have been replaced years ago.
    Last edited: Jun 27, 2012
  8. dw85745

    dw85745 Member

    Just went through this when flushing the copper lines to solder in a new line. The undersink valve had a lot of trash and would Not shut off.
    Removed the value and cleaned out the trash (minerals solids), but when reinstalling the value the value leaked at the nut.
    Wanted to put in a new value - using the same body assembly -- but could Not locate any of the old Eastman - Speed-flex values.
    Guess their out of business.

    I personally like the multi-turn values especially with hard water. If you turn the value 1/2 turn back after opening it, you have some play room to move the value back and forth and break the minerals loose if it stuck and you need to shut it off.
    Not real sure about the 1/4 turn angle ball values and how they will hold up over time (20+ years) where mineral content is high.
Similar Threads: Water Shutoff
Forum Title Date
Plumbing Forum, Professional & DIY Advice Replacing under sink, sweated, water shutoff Oct 7, 2014
Plumbing Forum, Professional & DIY Advice Can anyone explain this cold water shutoff valve phenomena Jul 30, 2014
Plumbing Forum, Professional & DIY Advice Main Water Supply Shutoff - Standard Valve Type Mar 11, 2014
Plumbing Forum, Professional & DIY Advice remote water shutoff Jan 30, 2014
Plumbing Forum, Professional & DIY Advice Leak detection and well water shutoff system Oct 25, 2013

Share This Page