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.

Low loss header v.s. Closely spaced tees

Options
fricard
fricard Member Posts: 18
Why would I want to use a low loss header for a system with a Burnham Aspen 155 boiler, seven zones of staple up radiant with plates, one small baseboard zone, one indirect water heater, and zoning with circulators. The radiant design calls for a low loss header. I have always used closely spaced tees and have never had a problem that I know of. There is a big price difference which I don’t mind spending if there is a performance benefit. Space is not an issue.

Comments

  • kcopp
    kcopp Member Posts: 4,448
    Options
    In addition to they look cool... You can do air removal, dirt separation and save some space.
    SuperTech
  • Jamie Hall
    Jamie Hall Member Posts: 23,635
    Options
    Another potential factor -- cost and experience. Not of the materials (closely spaced tees are going to be less!), but of labour. A low loss header can be installed more quickly and by less skilled help, and this can make a big difference, depending on your local labour rates.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • GroundUp
    GroundUp Member Posts: 1,956
    Options
    LLH take up WAY more space than CST and take twice as long to install in my experience. But they do look really cool and offer more versatility and function along with what I feel is a better hydraulic separation. The Caleffi versions leave a nice 1/2" port for a system sensor which I find to be an excellent place for a tridicator gauge.
    Alan (California Radiant) Forbes
  • john123
    john123 Member Posts: 83
    Options
    If you are trying to make a mod-con boiler as efficient as possible, would the closely spaced Tee's make it more efficient than the low loss header because the return water would be cooler. Does not the low loss header warm up the return water?
  • hot_rod
    hot_rod Member Posts: 22,472
    Options
    A low loss header is closely spaced tees, in a larger size. The temperature blend will be the same in either component.

    You have only 3 conditions possible in tees or seps. Equal flow, higher boiler or higher distribution. So the temperature blend depends on which condition. With multiple zoned loads, that mixed temperature
    , flow rate difference changes. Here is the math to predict those temperatures.

    My Lochinvar has a variable speed boiler circ, so the control will watch the boiler return and adjust for the lowest allowable return, does the Burnham? If your goal is the lowest possible return, best boiler efficiency, that is one measurable way to get it.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Alan (California Radiant) Forbes
  • hot_rod
    hot_rod Member Posts: 22,472
    Options
    the water doesn’t know if it is going thru tees or a vessel like a separator/ llh. One of these 3 conditions is present when flow is moving.
    How could it not be?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream