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Expansion tank that can handle more heat

CBRob
CBRob Member Posts: 283
in Domestic Hot Water
A home that I manage has a poorly placed expansion tank, it's on the cold side of the tank but close to a recirc pump that keeps it too hot.

I'll probably try to put a little heat trap loop before the tank but I'd like to know if there are dhw tanks that can handle more heat

Comments

  • JUGHNE
    JUGHNE Member Posts: 11,400
    How do you know it is getting too hot?
    Most true DHW exp tanks are rated for pretty high temps.
  • Zman
    Zman Member Posts: 7,611
    DHW expansion tanks can handle more heat than the occupants or the relief valve. What are the symptoms?
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • CBRob
    CBRob Member Posts: 283
    edited November 2019
    Just replaced it last year and it is full of water already.
    I'll take a pic tomorrow of how it is situated
    I'm guessing the failure is heat related...
    Could be something else.
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    What’s your incoming water pressure?

    There was an error rendering this rich post.

  • CBRob
    CBRob Member Posts: 283
    I have not put a gauge to it, but there is a regulator with a 65psi high end.
  • JohnNY
    JohnNY Member Posts: 3,317
    DHW expansion tanks are typically factory pre-charged to 40 PSI. Isolate and pump up your tank's air pressure. Problem solved.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
    Classes
    CBRob
  • DZoro
    DZoro Member Posts: 1,048
    What model of tank are you using? Is this on the domestic water? Boiler water? There are differences between DHW tanks and Radiant heating tanks.
    D
    CBRob
  • CBRob
    CBRob Member Posts: 283
    John was right, I just needed to pump it up.
    It's at 50 psi now and holding air.
  • CBRob
    CBRob Member Posts: 283
    DZ,
    I found the tank on the radiant heat was incorrect... same house.
    Swapped in a rx30 .

    Also noticed the circ pump installed with a vertical shaft, but I think that is ok with adequate psi in the system. I saw another discussion here at heating help that talks about pumps installed incorrectly
  • CBRob
    CBRob Member Posts: 283
    Can I use the flex2 dhw tank that I removed in another dhw application?
    It's not fubar from being exposed to glycol?
  • Jamie Hall
    Jamie Hall Member Posts: 25,991
    CBRob said:

    Can I use the flex2 dhw tank that I removed in another dhw application?

    It's not fubar from being exposed to glycol?

    No. Once it has been exposed to glycol, you mustn't use it for domestic (drinking) water.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    CBRob

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