(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 3 of 3

Thread: Hot Water Recirculation

  1. #1

    Default Hot Water Recirculation


    I need some advice on:

    1. Pump size and a good manufacturer/model
    2. Return pipe size and type of pipe (will pvc do OK?)
    3. Is pipe insulation required

    This is for a residential hot water recirculation system which has copper pipes.

    I have 3 bathrooms, the farthest is about 70 feet from the Hot Water heater. I would like to run a recirculation system to save water and to get the hot water faster.

    Any help/advice would be greatly appreciated.

  2. #2
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    New England


    I just retrofit a redytemp.com unit, really easy and very fast install (about 5-minutes!). Grunfos makes one that has also been recommended. Taco (probably the guts of most of them anyway) now makes one called D'Mand system. If it were me, I'd run either copper or pex as the return line, not pvc. I'm not a pro. I'd definately insulate all pipes, both hot and cold (the cold to prevent condensation).
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

  3. #3
    Plumber Deb's Avatar
    Join Date
    Sep 2004

    Cool Deb

    You cannot use PVC anywhere inside the foundation of a home for water distribution. PVC should never be used with hot water anywhere.
    If you are on slab and cannot run a return line, you will need a retrofit unit. I have never installed one of these, so can offer no opinions. If you can run a return line, you can install a recirc pump at the water heater.
    I like to keep all the water piping in a home the same if possible--things like galvanized and PB being the exception. I generally run a 1/2" return line. Pipe insulation? Depends on circumstances--crawls with alot of heat ducting stay very warm, insulating pipes helps little on systems on timers rather than thermostats, etc, etc. Grunfos and Taco hold the lion's share of the pump market around here. It seems like I replace alot of pumps, but there are alot of them around here. Vast geothermal resources exist here and virtually every application requires at the very least, a recirc pump.
    Check out the Grunsfos web site.
    The Pipewench


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts