Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Recirc loop for tankless water heater

Matthias
Matthias Member Posts: 38
Does anyone have an idea of how to install a hotel loop for a instantaneous/tankless hot water heater? We're using the Grundfos water saving system. What we're trying to avoid is having the tankless run the entire time the timer for the recirc loop is on? Thanks for the advise.

Comments

  • SWEI
    SWEI Member Posts: 7,356
    There are several options for doing this. Which one is best will depend on the length and heat loss of the loop (supply and return piping together) and the budget. Can you give us more details?
    Matthias
  • Matthias
    Matthias Member Posts: 38
    The furthest bathroom is about 75 feet away. There is no budget. I had thought about using the Taco D'mand system with smart sensor, which would shut the circ off when the water reaches temp. Not sure how to use the Grundfos recirc system with a tankless water heater.
  • SWEI
    SWEI Member Posts: 7,356
    So you've already purchased the Grundfos? If it's the one with the thermostatic EOL valves, beware of hard water. The Taco EOL valves have much larger passages and are designed to be easily cleaned.
  • Leon82
    Leon82 Member Posts: 684
    edited February 2016
    I use a 4 gallon minitank on mine with flow checks.

    It also acts as a buffer
    SWEInicholas bonham-carter
  • SWEI
    SWEI Member Posts: 7,356
    edited February 2016
    That is the solution which will work with just about any tankless. It costs a bit more, but it's far less fussy.

    Some of the latest tankless models are starting to directly support recirc. A few even include a pump.