(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 11 of 11

Thread: Electric WH T&P Valve

  1. #1
    DIY Junior Member
    Join Date
    Dec 2008
    Location
    Burbank, CA
    Posts
    21

    Default Electric WH T&P Valve

    I want to install an electric water heater in an interior closet. Code requires a T&P valve discharging to a drain but there is no drain available and it's a long way to the outside of the building. Is there an electric water heater equivalent to the Watts 210 valve for gas water heaters?

  2. #2
    General Engineering Contractor ballvalve's Avatar
    Join Date
    Dec 2009
    Location
    northfork, california
    Posts
    3,258

    Default

    If no permit I would discharge into a 30 gallon steel container with a hole in the lid. I have never had a run away electric water heater in all my years, and most drips are just bad valves. For that matter you could set another "open" water heater next to it and discharge into the cold inlet. I see 40 gallon rigs for $199 now, and thats the cost of a few good garbage cans.

    That also gives you your next water heater ready to go.

    Running a pipe is a better idea, of course. And legal, if you care.

  3. #3
    DIY Junior Member
    Join Date
    Dec 2008
    Location
    Burbank, CA
    Posts
    21

    Default

    Thanks, Ballvalve. I do care about legal. I've never heard of a runaway electric WH either. I've also been told there is safety circuitry built into them that prevents it. Still, the manufacturers and the code people must think there is a need for T&P valve, they both require it. I looked all over for an equivalent to the Watts 210 but for electric, seems like it wouldn't be that hard to make. Can't find one anywhere. Unless someone else has info on one, I'm going to conclude they don't exist.

  4. #4
    Homeowner
    Join Date
    Jan 2010
    Location
    Alabama
    Posts
    1,174
    Blog Entries
    1

    Default

    Both gas and electric water heaters have a high limit ECO. (energy cut off).

    If you care about it being legal then I suggest either calling a licensed plumber and or your local plumbing inspector about the legal installation of an electric water heater in a location that has no suitable drain.

  5. #5
    Moderator & Master Plumber hj's Avatar
    Join Date
    Aug 2004
    Location
    Cave Creek, Arizona
    Posts
    25,605

    Default

    quote; I've also been told there is safety circuitry built into them that prevents it.

    When the water heaters started to come with ECOs, the plumbing codes in the Southern states believed the statement that it made heaters as safe as light bulbs so they did NOT require T&P valves. Subsequently, Domestic Engineering magazine had articles EVERY week about them exploding and destroying homes, AND people. One particularly disturbing one was a teenager who was sleeping on the other side of the wall when the heater exploded and decapitated him. Electric heaters DO go wild, and yours might be one that does it. How long do you think it would take a 3/4" pipe under full pressure to fill a 30 gallon barrel OR even a 40 gallon "empty" water heater? When first fill a heater it only takes a matter of minutes to fill it.
    Licensed residential and commercial plumber

  6. #6
    Homeowner
    Join Date
    Jan 2010
    Location
    Alabama
    Posts
    1,174
    Blog Entries
    1

    Default

    In the last 4 years two water heaters have blown up in Phoenix,AZ.

    Here is a link to water heater explosions documented around the country.

    Check it out....

    http://www.waterheaterexplosions.com/explosions.html

  7. #7
    General Engineering Contractor ballvalve's Avatar
    Join Date
    Dec 2009
    Location
    northfork, california
    Posts
    3,258

    Default

    most all of those are fires, usually gas related. I would try and always avoid a gas water heater IN the home.

    No one suggests this guy not use a relief valve, its just about where to go with it.

  8. #8
    Test, Don't Guess! cacher_chick's Avatar
    Join Date
    Jan 2008
    Location
    Land of Cheese
    Posts
    3,140

    Default

    Unless the water heater is on the 2nd floor, I can't imagine why running a drain line would be such a problem.

  9. #9
    Homeowner
    Join Date
    Jan 2010
    Location
    Alabama
    Posts
    1,174
    Blog Entries
    1

    Default

    Quote Originally Posted by cacher_chick View Post
    Unless the water heater is on the 2nd floor, I can't imagine why running a drain line would be such a problem.
    How do you plan to cross hallways or doorways with slab on grade construction.

  10. #10
    Homeowner
    Join Date
    Jan 2010
    Location
    Alabama
    Posts
    1,174
    Blog Entries
    1

    Default

    I would install the water heater in a pan without a drain. Pipe it to a wags valve positioned in the pan. I would install the water heaters relief line into the pan. I would install another T&P valve at a lower operating set point at a higher elevation so I could install a gravity drain to the outside.

    Of course after pre approval from the plumbing inspector.

  11. #11
    Test, Don't Guess! cacher_chick's Avatar
    Join Date
    Jan 2008
    Location
    Land of Cheese
    Posts
    3,140

    Default

    Quote Originally Posted by Hackney plumbing View Post
    How do you plan to cross hallways or doorways with slab on grade construction.
    It's one of those questions that have different answers depending on where you are located.

    Where I am, there are no houses built slab on grade- only crawlspace or basement.

Similar Threads

  1. Combining an electric Tank with electric Tankless
    By Dkrasko in forum Tankless Water Heater Forum
    Replies: 15
    Last Post: 03-27-2014, 08:24 AM
  2. how does electric sprinkler valve work?
    By oldanbo in forum Irrigation / Sprinkler Forum
    Replies: 17
    Last Post: 06-22-2009, 06:48 PM
  3. Combining an electric Tank with electric Tankless
    By Dkrasko in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 14
    Last Post: 11-28-2008, 03:14 PM
  4. electric variable flow valve
    By Tinmaniii in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 11
    Last Post: 10-19-2008, 07:17 AM
  5. Replace dinosaur electric with electric, power or direct vent?
    By mr_littlejeans in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 14
    Last Post: 05-02-2008, 03:36 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •