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.

non ferrous circs for non-oxygen barrier radiant?

paul_81
paul_81 Member Posts: 27
in Radiant Heating
Recently isolated a 1990's butyl rubber radiant system from the boiler using stainless HX.  Original Grundfos 15-42 cast circs were still running, two now have failed - old boiler was a electric thermal storage unit - 800 gallon tank.  Will new cast circs (grundfos 15-58) have a chance of living a long productive life as the 15-42 did or should we insist on using stainless circs?  Now that the circs are the only iron part on the radiant side of the HX, will they degrade faster?

Comments

  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 4,206
    Oxygen

    Oxygen will deteriorate the cast iron circulators on the radiant side if the tubing is non-barrier.  Replace them with bronze or stainless steel.  
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
This discussion has been closed.

Categories