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3 coil indrect

Unless you want to run glycol in the boiler too, you will need 3 heat exchangers.

It would probably be cheaper to use a 2 coil indirect plus a flat plate heat exchanger rather than a 3 coil indirect.

You could replace one of the pairs of closely spaced T's in a primary loop with the flat plate heat exchanger to get the third input.

Comments

  • highlander
    highlander Member Posts: 10
    3 coil indrect

    concider a 3 coil indrect dhw tank for a home with radiant floor heat.bottom coil is for solar input, center coil is for mod con boiler input and top coil is for radiant loops.Tank may have to be large, 100 gal. Will it work? has anybody seen a tank like this?
  • Uni R_2
    Uni R_2 Member Posts: 589
    Would this work?

    http://www.acv.com/int-en/03_05/243/app.rvb

    If so, let Triangle-Tube know that there is a market for it here - get them to start bringing them over.

    The 400 litre (100 gallon) size exists already.
  • Joe Brix
    Joe Brix Member Posts: 626
    a 3 coil tank would be pricey

    Wouldn't a 2 coil be enough if you pipe it P/S for the 2 heat sources: solar and mod/con? Several stock 2 coil units out there.
  • hot_rod
    hot_rod Member Posts: 22,103
    triple coil indirects wouls be nice to have

    I suspect a 3 coil 80 gallon tank would be in the excess of 2 grand, however.

    Looking at the cut aways of those Euro triple coil tanks they have a boatload of coil in them. They look to be at least 1-1/4" diameter coils too.

    Lots of HX surface makes for a great tank. Able to harvest low temperature solar, able to take a lot of boiler input and perform quickly. Easy to pull low temperature radiant off a large coil, etc...

    Creative piping could get you there. Maybe a 3 way zone valve, or an external HX.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • highlander
    highlander Member Posts: 10
    3coil

    part of the idea is to have less equipment out side the tank. solar will provide for the heat loop without running boiler loop.tank may also act as buffer for boiler short cy.


  • hot_rod
    hot_rod Member Posts: 22,103
    I suspect listings and

    the number of tanks that would be sold in this market is what keeps those large tanks on the other side of the pond.

    There was a dealer at the REX show in CT. last month that had a 750 or 1000 litere cut-away triple coil tank in his booth. That's the first one I have actually seen in the US of A. Didn't sound like he had plans to import any.

    hot rod
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • highlander
    highlander Member Posts: 10
    3coil

    an HTP phoenix with coil top and bottom is needed.solar loop is glycal and cant share loop with boiler
  • Ron Schroeder
    Ron Schroeder Member Posts: 998


    Will the solar be drainback?
  • highlander
    highlander Member Posts: 10
    solar

    solar loop is closed gly. the main reason for doing a system like this is space savings. this house is on slab, no basement, small utility room to work with. This progect is on the west coast, frost lines are not deep so many new homes have no basement.
This discussion has been closed.