Replies

1. 
   BillHartmann | Jan 23, 2008 03:16am | #1

   If the water was steaming hot then the WH burner control probably failed.

   If it was cold water either the safety valve failed.

   Or if she has a pressure reducing valve it failed.

   If she has a PRV it will be near the main shutoff and you will most likely have one also.

   http://tinyurl.com/3am23b

   It will a direct acting one similar.

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   .
   A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
1. 
   musashi | Jan 23, 2008 03:54am | #3

   Thanks for your replies.

   There is no pressure reducing valve, as far as I know.  (I don't have one over here.)  The water coming out was steaming hot.  I turned off the cold supply valve just on top of the heater.  I closed it tightly, and I checked to make sure that it was attached to the cold pipe, and not the hot one.  Still, it kept dripping out of the pressure release valve. 

   Some minutes later, I turned of the cold supply farther upstream, and the dripping stopped.  So, with whatever else is wrong, the cold shutoff valve atop the heater does not close. 

   You suggest that the burner control failed - is this a part replacement?

   (I am in over my head here - I just want to know what to tell her.)

   Thanks.Outside of a dog, a book is a man's best friend. Inside of a dog, it's too dark to read.
   -Groucho Marx

1. 
   honeyrider | Jan 23, 2008 04:09am | #4

   does the relief valve feel like it is closing properly, or weak? There is usually a lever on the top so that you can try it. If this seems okay I would suggest checking the temperature of the water coming out with a thermometer to see what temp it is. If it is close to  boiling and the flame has not gone off then the burner control is faulty. Water temperature above 140 F will cause burns within about 5 seconds so be careful. If in doubt shut it down and call a professional.

2. 
   BillHartmann | Jan 23, 2008 05:08am | #5

   You have lots of water in the all of the hot water supply lines that will slowly drain out. So the water valve might have shut off. Hard to tell without seeing the flow.Also if anyone turned on any water at a faucet with both the hot and cold open (and it is almost automatical if it is a single lever faucet) then you will be back flow from the cold water line to the hot water and back out the safety valve.The gas control valve can be replaced, but it is often not practical to do so.Hard telling what to recommend. If it was mine I would replace the safety valve and monitor it.Start by checking it every 5 minutes are so and see if the burner cutsoff.Beinng a "little old lady" it is not easy to recommned that.How old is the WH? WH has lifetimes from less than 10 to more than 20 years, a lot depends on the local water and usages. If it was older than say 8 years I would suggest going ahead and replacing it..
   .
   A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.

1. 
   musashi | Jan 23, 2008 05:42am | #6

   I thank everyone for the suggestions. 

   As I said, this is over my head as a repair.  I did 'damage control', got all the water to stop leaking and turned off the gas, and passed all the information I learned here over to her. 

   It's now up to her and her plumber.

    

    Outside of a dog, a book is a man's best friend. Inside of a dog, it's too dark to read.
   -Groucho Marx

2. 
   wallyo | Jan 23, 2008 03:28am | #2

   I was just thinking about this the other day.

   We put in a gas water heater, at two in the morning a few years later we hear water running, check the bathroom -kitchen nothing. Open the garage door, steam, the valve poped open.
   Asked at the plumbing supply house was told that the valves just fail sometimes. Got a new one put it in no problem still have the same heater.

   If it is newer I'd say it probably the valve but observe caution it could be burner control etc.

   Messed up a bunch of wood flooring in the living room also.

   Wallyo

3. 
   roger g | Jan 23, 2008 05:48am | #7

   It's called a TP valve (temperature and pressure valve). It is designed to open if there is too much pressure or too much heat. Too much heat also raises the pressure.

    The valve might be working properly which means you have a problem either with temperature or pressure. You might just have a faulty valve which decided to open so you need to change that.

    Sometimes I hear of an intermittent pressure problem and that is sometimes solved by installing a pressure tank which absorbes some of the pressure.

    

   roger

4. 
   DanH | Jan 23, 2008 05:54am | #8

   A water heater T&P valve blows for one of three reasons:

   1) Too hot.
   2) Too much pressure.
   3) Defective valve.

   My money would be on too hot -- the thermostat likely failed and the tank overheated.

   So most likely a plumber is needed.

   If your view never changes you're following the wrong leader