Flexible supply lines on a gas water heater

Discussion in 'Plumbing Forum, Professional & DIY Advice, Tips & ' started by Ian Gills, Oct 24, 2007.

  1. Ian Gills

    Ian Gills Senior Robin Hood Guy

    Messages:
    2,780
    Location:
    USA
    My gas water heater currently is plumbed with rigid copper pipe for the water and iron pipe for the gas.

    Were it to be replaced by a licensed plumber, and flexible SS lines used for the water and a flexible gas line for the gas, what would stop the water heater from rocking or tipping over if it were knocked?

    Or are water heaters very stable and heavy when full of water?

    Just a curious thought I had the other day.
    Last edited: Oct 24, 2007
  2. Gary Swart

    Gary Swart In the Trades

    Messages:
    7,310
    Location:
    Yakima WA
    Some states, California is one I think, require water heaters to be strapped to the wall to prevent tipping in case of earthquakes. As far as stability under normal conditions, you would be hard pressed to tip a full tank over. If it were to tip, I don't think a ridged pipe connection, which would be at the base of the tank, would help very much. Further, I believe a solid gas line connection to any appliance would be subject to breaking in case of any movement. You couldn't even have a gas stove that was recessed in a counter because you couldn't connect the pipe with the stove in position. Flex gas lines are pretty standard fare with gas appliances.
  3. Peanut9199

    Peanut9199 Customer Service Manager Plumbing Wholesale

    Messages:
    875
    Location:
    Ontario, Canada
    It wouldn't rock or move on it's own.
    The Water supply lines are 3/4", to find 3/4" ss lines would be difficult and you usually run up and along the floor joints.
    With flex lines you would have to secure the pipes somewhere as you now have no supported vertical lines.
    The SS gas lines are normally used with appliances that need to be moved like a stove. You would still need to run black pipe to a certain piont and then change to flex.
  4. Gary Swart

    Gary Swart In the Trades

    Messages:
    7,310
    Location:
    Yakima WA
    I forgot to add a mention of the flex water lines. They are the only way to go. It is just a PITA to connect solid lines. Just use reasonable care so as not the kink them when putting a bend into them.
  5. flex lines are code in some areas

    Some areas like Colorado have soil that can rise like bread
    and you have to use the flex gas line and flex water
    lines to let the heater "breathe"

    strapping it to the wall is necessary in
    earth quake zones...

    I always use the flex gas lines...

    when you take apart an old water heater and the gas line jumps about 8 inches. when the union is disconnected,

    you know that the old black gas line was under a lot of stress
  6. ilya

    ilya In the Trades

    Messages:
    105
    Location:
    Akron Ohio
    "You know the old gas line was under a lot of stress" This would cause a joint to fail sooner, yes?
  7. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego
    I don't know how much testing has been done on water heaters on the shake table, but I assume it has been, because CA codes are adamant about earthquake straps.....
    Some older houses which are not strapped to the foundation have moved right off the foundation. A water heater weighing a measly 500 pounds would go over in a heartbeat. Flex lines on the gas and water are in hopes that things can shake around quite a bit and not break a water or gas connection.
  8. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,315
    Location:
    Cave Creek, Arizona
    You have NEVER tried to tip a water heater which was full of water, or you would not even be asking the question.
  9. Ian Gills

    Ian Gills Senior Robin Hood Guy

    Messages:
    2,780
    Location:
    USA
    This is an old post. But at 250 pounds, I'd easy knock a 40 gallon over (320+ pounds) with an odd stumble.

    It would at least move if I fell against it.
  10. Terry

    Terry Administrator Staff Member

    Messages:
    14,819
    Location:
    Bothell, Washington
    You're not going to be knocking over a tank that is connected with flex connectors.
    I sometimes loop a connector to the two inlets to carry or lift a tank.

    The reason some states require flex in earthquake zones, is not the worry that a tank will fall over, but that the gas connection will crack or break, and light up from the pilot light outside the confines of the burn chamber inside the heater.
  11. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego
    If your whole house...and the ground under it...suddenly moves two feet to one side, when it stops and goes back the other way, trust me....without a strap that water heater will keep going! Don't underestimate the power of ma nature!
  12. Gsalet

    Gsalet George the Plumber

    Messages:
    83
    Location:
    San Francisco
    If the ground moves 2 feet in any direction, The water heater is the least of your worries!! Here in San Francisco we expect the water heater to still be attached to the wall after it has fallen<GRIN> on a more serious note I have seen the difference between a water heater breaking the gas and water lines or not during a earthquake is just a little piece of plumbers tape. My personal opinion is that it keeps the waterheater moving with the building instead of against it when the building returns to it's normal position (Hopefully)
    As far as flex water supplies I don't like them, they leak just as often as a solid connection in a earthquake. But just about anyone can install them No Plumber required
  13. Terry

    Terry Administrator Staff Member

    Messages:
    14,819
    Location:
    Bothell, Washington
    The code on the West Coast is to Earthquake Strap the water heater.
    It's not like the connectors are the only thing holding them in place.
Similar Threads: Flexible supply
Forum Title Date
Plumbing Forum, Professional & DIY Advice, Tips & Flexible (roll) copper for bathroom supply lines? Sep 21, 2010
Plumbing Forum, Professional & DIY Advice, Tips & Do you pros use flexible supply lines? Any tips? Nov 11, 2007
Plumbing Forum, Professional & DIY Advice, Tips & Can I use flexible supply lines from shuttoffs to shower valve? Jun 8, 2006
Plumbing Forum, Professional & DIY Advice, Tips & How durable are flexible supply lines? Apr 12, 2005
Plumbing Forum, Professional & DIY Advice, Tips & Can you use flexible rubber cuppling at bathroom sink drain? Photo May 28, 2014

Share This Page