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Quick TT indired question

Jimbo_5 Member Posts: 218
To be on the safe side, is it ok to work on the DHW piping atop the Smart-40 with no pressure on it?  Meaning the core will have its 12 lbs connected to the boiler but the outer tank will have water but no pressure.  It has just thrown me off kilter a bit wondering about this, since I have never had to repipe the DHW after install before on a "tank-in-tank."


  • adambuild
    adambuild Member Posts: 414

    Hi Jimbo,

    Your description seems backwards, but if I understand corectly you want to work on the DHW with no pressure on it while the outer (boiler water) tank is full, right? That's no problem. The only scenario warned against in the manual is filling the boiler section of the tank before the DHW. If you're still not 100%, call TT tech support and confirm.

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