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Insulation in crawl space

dpenny
dpenny Member Posts: 24
edited October 2 in Gas Heating

I just had a Navien NHB-80H installed about 2-3 weeks ago now to supply 75feet of baseboard in a 1900 sq ft hose, we have mild winters, 20-30 for maybe two weeks straight, once twice a winter. Problem was could not water hot enough with old Rianni system

We've now had a couple of nights now with 59-62 outside. I've got nite time thermo set at 64, switching to 70 at 6am. House has been fine when I'm up at 8am. Of course not even "testing" the NHB yet.

But I do have a Q about insulating partial piping in crawl space. In the earl morns (above): boiler internal temp water is 175-181. External stat in hot supply pipe (1") says ~170. In house at baseboard entrance by fins hand stat says 160.

a) is this 10 deg drop to be expected from 22' run in crawl space? It's gotta be ~60 in there.

b) what can I expect if I crawl down and insulate these 22' of 3/4 copper tube? how much of the 10 deg drop will I gain?

Best guesses please. Don't ask for more details.

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 26,407

    That 10 degree drop is more than I would expect — if the water is flowing. It's remarkably difficult to get an accurate estimate of metal surface temperatures — never mind the temperature of the water inside — and I'm of the mind that it isn't real.

    Insulation won't hurt. But I would doubt that it would make much difference, either.

    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • dpenny
    dpenny Member Posts: 24

    Thanks UR comments in earlier & private eMails were straight on.