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    Old System to new (11 Posts)

  • ricking ricking @ 5:48 PM
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    Old System to new

    My System, or what is left of it.


    Installed in the house around the mid 40's. Radiant heat embedded in plaster on the ceiling. Return line 1 ¼ as well as feed. 3/8 copper snaked on ceiling at approx 10 inch centers. The house is 1600 sqf. All one level. Every room has the heat system in it so all 1600sqf is heated by it. It is one zone. One thermostat. You can shut off rooms by closing manually the valves placed throughout the house. I will include pics.


    When I purchased the house, there was a rather large old oil boiler consuming about 1 ocean going tanker of oil every month. One winter later I replaced it with a Budures wood/coal fired boiler with a Superhot 30kw electric as backup. The wood boiler was rated at 96,000btu and the electric just over 100,000. The wood boiler worked very well when the outside temp was below freezing. I could keep the water temp at 140 without a problem. But she ate a ton of wood. The electric would work well as it had 6, 5000w elements that modulated to demand. All in all the system worked great. As time passed, I got sick of cutting firewood. As more time as passed, I am sick of paying hydro. I do now believe that these two units were over sized.


    Everything is ripped out. Only 2 pipes sticking out of the ceiling. Return and feed.


    I live in Squamish BC Canada. Half way between Vancouver BC and Whistler BC. We have 4 defined seasons here with winter lows that have hit lows around 0 in the past, but with weather as it has been going, the lows we hit are around 15. But not sustained for a long period of time. May be a week and a bit at most. And not very often.


    I have been attempting a few heat loss calc's and have come up with some numbers. Slant-fin has an app that I tried. Came up with 44,000. I used temps 72 for indoors and 30 for out. Measured every room, window, door, outside walls and everything else that wasn't moving.


    Using a simplified method at 40btu per sqf for a uninsulated house or very poor, that number is 40 times 1600 = 64,000.


    Well, my old shack is fairly well insulated with double glazed windows (albeit older ones) so I figure to use 30btu times 1600 which gives me 48,000.


    If I am off tract, please let me know.


    Have been researching boilers for at least 2 months now and became more confused with the more I read. Until I found this site. Right now, I have my heart set on a Triangle Tube. Was looking at a Navian as they are popular here but not impressed after some research.


    Thinking of just going with the straight boiler. No DHW for now. Want to keep it simple and warm. The Prestige Solo 60 NG is looking like a fit.


    Please keep in mind that I am NOT a heating guy. I just would like to do research before attempting to do it or hiring someone.


    Thanks in advance for your input.


    Rick
  • Zman Zman @ 8:21 PM
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    Yup

    So, what do need us for. It sounds like you a have solid grasp on this.
    I think your heat loss calc is a bit high. It is kind irrelevant as the boilers don't come that small.
    I think using the outdoor reset function on the boiler will improve comfort and efficiency greatly.
    You might consider putting remote zone valves and t-stats in place of the isolation valves in some of the rooms. If the system is well balanced now you may not need to.
    The triangle tube is a great choice.
    Carl
  • Gordy Gordy @ 11:09 PM
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    One question

    The 140* supply temp off the boiler I hope is mixed down for the radiant ceiling panels.

    Should not need 115 on a much colder day than you will experience.
  • icesailor icesailor @ 6:34 AM
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    Radiant Ceiling:

    That was a first class system that never reached its potential. It needed Outdoor Re-set (ODR) and must have had a a thermostatic mixer for the radiant part. The water going to the radiant part should not ever go above 150 degrees or it can crack the hard finish plaster. Perhaps someone before you screwed it up and parts are missing. I know that you are exaggerating your fuel consumption because the systems I have seen aren't that bad on fuel unless someone screws them up. Old systems usually only had a couple of inches of vermiculite insulation above the coils. If there is a second floor, add more insulation.
    If someone removed all the piping so that there are only two pipes sticking through the ceiling. I hope that you didn't get the poop prize because it sounds like some dubber didn't know what they were doing. Now that someone has removed all the piping, it will be hard to figure out what the old dead guys had in mind and what they did.
  • ricking ricking @ 2:00 PM
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    Thanks for the replys

    Good to know that at least I am heading in the right direction. Thanks.
    So a little more info and hopefully I can attach some pics.
    There was and is an outdoor temp sensor. Is that something to do with a ODR?
    The system did heat the house very evenly so I would asume it is balanced fairly well?
    As far as 140 degree water going directly into the system, it did not. There was a rather old Honeywell flow control valve that the indoor themastat was conected to as well as the outdoor temp sensor. I hope the pics post here. When I installed the wood boiler and electric, everything was left oringinal. Just changed the heat source. Saved the old piping for info to remind me or a installer what the oringal dead guys designed. It was actually installed by Cheveron way back then. Guess they wanted me to burn their oil.
    Insulation. Original was and is 8 inches of rockwool and 2 inches of shreaded ceader bark. Over that several years ago I added 10 inches of fiberglass pink. Think I am around R40 up there.
    So. I would really like a new updated design with the oringal setup in mind. You guys are the pros and if you charge for design, I will pay.
  • ricking ricking @ 2:43 PM
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    Can't seem to post pics

    If you would like to see some pics, might have to e mail them.

    R
  • Gordy Gordy @ 8:33 PM
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    Radiant ceilings

    Are top notch I have them in my home from the early 50's. I even have the original chase brass and copper propaganda from the era. You can find same literature here in the library.

    Ice is right though the original supply,return piping is crucial in its design for air removal of the ceiling panel coils along with flow characteristics.

    Mine is piped parallel piped that way head is self balancing, it flow rates are not so balance valves for each loop is the norm.

    The main return is in the basement floor with risers in various locations to collect the loop returns. Air will always collect in the risers of the return for removal when purging, and during initial fill. While the main supply runs across the basement ceiling. Each loop has a valve to bleed air in the basement on the return.

    Mine has the original taco paneltrol mixing valve. My boiler is set to 160 no outdoor reset. But it almost follows a reset curve when in operation. The longer the heat call the warmer the supply water gets, but has never exceeded 115* at outside design temps -10.
  • SWEI SWEI @ 12:18 AM
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    It almost follows a reset curve

    Some kind of semi-magical optimization of thermal mass and boiler sizing?
  • Gordy Gordy @ 1:35 AM
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    Don't laugh

    Just a good meld of emitter design, mass, piping design, and proper circ sizing . It's really uncanny how the system responds even with a boiler x2 for size....... Simple and elegant one circ one t stat.
    This post was edited by an admin on May 12, 2013 1:38 AM.
  • SWEI SWEI @ 11:36 AM
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    Not laughing

    just being impressed by good old applied engineering.  Nice.
  • Zman Zman @ 8:28 PM
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    Pretty simple

    Using a triangle tube 60 with no domestic water there is not much to design.
    You can pretty much go by the diagrams in the installation manual.
    Sizing the heat size circulator will take some consideration. Do you know what was installed before.

    Carl
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