GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter X Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

On-demand hot water recirculation system

bradrh | Posted in Mechanicals on

One of the criticisms I’ve read for the on demand HW recirc system is that they take too long to get hot water. Never having used one of these I’m wonder what is too long? I’m looking at the readytemp TL4000 which has a taco model 008 pump and my quick estimate is about 35 sec. That seems reasonable to me.
The TL4000D is $435 for pump and controls. Any other suggested alternates? This is for new construction.

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. GBA Editor
    Martin Holladay | | #1

    The on-demand pump will greatly lower the wait time -- from unacceptably long to acceptable.

    Here is a link to an article on this topic: Hot Water Circulation Loops.

  2. Jon_R | | #2

    If you want fast, the TacoGenie 0011. Or a point of use heater for ~3 second response.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |