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  1. Replies
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    Chilled beams

    First- research what, exactly, these "chilled beams" are. What you'll likely find is thay are an updated version of the old 1960 Carrier ceiling mounted induction unit. They DO NOT provide any sort...
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    Surprised to see this thread still popping up...

    Surprised to see this thread still popping up after a year. Thanks to some for the feedback, although most of the comments still "sound" like the same sales hype we are getting from the sales reps...
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    Staple-up radiant floor heating

    You'll be hard pressed to get local help around Gabriola Island - I'm in Vancouver and it's tough finding any decent radiant guys around here, although my scope is mainly large commercial system...
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    Or look at your budget for the geo, and see how...

    Or look at your budget for the geo, and see how much money you can spend out of that with upgraded high performance windows, police up all the infiltration and cracks, add more roof and wall...
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    It's always interesting to see the second...

    It's always interesting to see the second guessing that goes on, but always, always start with the initial load calculations, building occupancy numbers, and basics, Like CXAgent's Post. A lot of...
  6. UK Building Services

    Start here: http://www.cibse.org/ and then start googling- they have much more stringent Codes and Design Standards over there, plus all the local jurisdictions with their own spins on the Carbon...
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    Yes, that would be the High school in South...

    Yes, that would be the High school in South Richmond. I don't recall what issues there were on THAT one during backfilling that I may have mentioned - there was another project in Richmond - the...
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    McQuay Templifier

    They are also known as a heat pump chiller- basically a glorified heat recovery chiller with a reversing valve for the refrigerant cycle so they can be used for heating and cooling in a water source...
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    Yes, I am

    I only drop in here from time to time. I still exist, at least the bills still get mailed to me.
  10. Don't forget the mean radiant temperature from...

    Don't forget the mean radiant temperature from building surfaces, especially around the crappy perimeters on most buildings. In a cold climate, the inside surface of a double glazed window can be...
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    Depending on your location YES, you can do both...

    Depending on your location YES, you can do both radiant heating and radiant cooling from the same system. The key is that the most effective, economical, and lowest energy use HVAC system is the...
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    Why not use electric radiant ceiling panels? No...

    Why not use electric radiant ceiling panels? No baseboard fin to collect munge and dirt, clean installation, and more comfortable. Try these:
    http://www.thermalinc.com/comfort/cp.htm...
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    Is there any way you can reduce the cooling...

    Is there any way you can reduce the cooling loads? That is the biggest task- reduce the loads first by working with the Architect and controlling solar gains and other heat gains to the space.
    ...
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    Depends on the right numbers being used. If you...

    Depends on the right numbers being used. If you used the insulation value of the roof and walls straight-up, there may be a significant error depending on how much thermal bridging there is in your...
  15. Thread: geothermal heat

    by gmcd
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    Illinois: heating dominated climate, which means...

    Illinois: heating dominated climate, which means the geo-exchange system will have to do way more heating over the year compared to cooling. Therefore the geo-exchange side (ground side system)...
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    My stuff is all hydronic heating and cooling...

    My stuff is all hydronic heating and cooling coils, no gas sections. The only controls connections are to the VFD's running the supply and exhaust fans. Simple.

    We specified the normal neoprene...
  17. Insulate your warehouse. And I'll bet the slab...

    Insulate your warehouse. And I'll bet the slab on grade wasn't insulated either. Do a blower door test and seal up all the air leakage cracks. Check out the "Solarwall" product for ventilation air...
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    Just had five of them planted on a roof a couple...

    Just had five of them planted on a roof a couple months back- custom heat recovery ventilators in the 5,000cfm to 10,000 cfm range. The only issue I had was that we specified coated acoustic...
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    The most energy efficient HVAC "systems" used in...

    The most energy efficient HVAC "systems" used in Europe are high performance windows, better wall details to eliminate thermal bridging, and exterior solar shading. The whole idea is to reduce the...
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    I'd also suggest the Building Science websites at...

    I'd also suggest the Building Science websites at http://www.buildingscience.com/bsc/ as well as the PassivHaus design approach here: http://www.passivhaus.org.uk/ Do some serious research and...
  21. Thread: Fabric Ductwork

    by gmcd
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    The reason I can so quickly "find" those things...

    The reason I can so quickly "find" those things out is that I have an extensive library on radiant systems, and DOAS systems, and I've corresponded with Dr. Mumma in the past, and have his website on...
  22. Thread: Fabric Ductwork

    by gmcd
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    That's from Dr. Mumma's website at Penn State...

    That's from Dr. Mumma's website at Penn State University, it's not software, it's a screen-shot from their local DDC controls system that shows the DOAS operations graphic. You can use regular air...
  23. Thread: Fabric Ductwork

    by gmcd
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    Kurrodo- I know how radiant slabs and CCC works -...

    Kurrodo- I know how radiant slabs and CCC works - been designing them for a lotta years now. It's just that the best combination when using a radiant ceiling emitter is to use a low level...
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    There are very limited choices for good radiant...

    There are very limited choices for good radiant slab simulation and calculation tools. This is one specific source:

    http://www.empa.ch/plugin/template/empa/*/5383/---/l=1

    Some high-end...
  25. Thread: Fabric Ductwork

    by gmcd
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    I'm not at work right now so I can't attach some...

    I'm not at work right now so I can't attach some sample pictures, but there are various ways of doing it:

    1. Cast supply air ducts in the slab to get to floor registers- use "Eccoduct" as it's...
  26. Thread: Fabric Ductwork

    by gmcd
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    2,251

    Kurrodo: is the concrete core conditioning a...

    Kurrodo: is the concrete core conditioning a "floor" or a "ceiling" radiant surface? I'm not a fan of fabic ducts except for specific applications. They can be a dirt collector in shops and...
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    Nik99: Chilled beams are a completely different...

    Nik99: Chilled beams are a completely different animal compared to radiant panels and radiant slabs. It's like comparing packaged rooftop unit VVT to dual duct VAV central systems. They both blow...
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    HvAckid82- exactly- remove the risk of...

    HvAckid82- exactly- remove the risk of condensation and what's the issue? Radiant cooling systems MUST operate with surface temperatures above the ambient indoor dewpoint. All commercial HVAC...
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    Nik99- You need to be more specific than just...

    Nik99- You need to be more specific than just passing on an opinion with no sources or references. Show me a perfectly comfortable operating VAV reheat system, or other conventional system first. ...
  30. Replies
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    Nik99- like what "problems"? I am aware a a very...

    Nik99- like what "problems"? I am aware a a very few early radiant cooling panel installations that went awry, but mainly due to lack of designer edication and indoor cooling load issues. There are...
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    In Europe, where radiant cooling is pretty well...

    In Europe, where radiant cooling is pretty well established, the sheets of capillary tube radiant mats that they use come with a small dewpoint sensor built right, in to reset the cooling water...
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    Carnak: Yes those are all what I term "technical...

    Carnak: Yes those are all what I term "technical school" level courses that provide great technologist type courses and people, but no "engineers" ever go to those schools after their university...
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    Shophound- yes- talk to any of the PE Mechanical...

    Shophound- yes- talk to any of the PE Mechanical engineers you know and ask how many even had that third year elective HVAC course available at their school/university, and if they did, did they take...
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    As a mechanical engineer who has had close to 30...

    As a mechanical engineer who has had close to 30 years of "on the job training", I understand and agree with the original post that started this thread, and HVACBear provided the reason that the...
  35. Thread: make up air

    by gmcd
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    High-rise building? What about the smoke control...

    High-rise building? What about the smoke control and corridor ventilation Codes? Are you dealing with make-up air for individual apartment suites? I hope the individual heat pumps are sized to...
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    Anyone got any comments, good, bad, or...

    Anyone got any comments, good, bad, or indifferent regarding these types of distributed DX systems? Daikon, Mitsubishi, Colt, etc. are flogging these systems as the latest and greatest solution to...
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    Use a passive plate type or heat pipe coil

    Unless there is a need for de-humidification, and for a bathroom ventilation application why not look at a plate type air to air heat exchanger, or a heat-pipe coil- absolutely zero leakage or risk...
  38. Thread: Green Engineering

    by gmcd
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    Energy Codes for Buildings First

    Let's start with some real simple baseline energy codes that specifically state a maximum energy intensity in Kwh/sq.ft/year, period. The ASHRAE 90.1 energy guidelines are a moving target the way...
  39. Thread: Radiant Cooling

    by gmcd
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    Getting goats

    The fundamental issues that carnak talks about are true. Radiant cooling is a sensible cooling temperature control system, it doesn't de-humidify- you still need an air system to do that. Just like...
  40. Thread: Radiant Cooling

    by gmcd
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    Radiant cooling in the Pacific NW

    There are at least five large scale radiant cooling systems operating successfully in the Pacific NW right now, mainly institutional and one commercial office building. There are also quite a few...
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    Radiant heating ceiling

    As long as the copper tubing is in good condition, this will be a fine, comfortable heating system. As with any older house, the first thing to do is to police up the envelope- seal leaks, improve...
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    Absolutely

    Most building codes require a minimum air change rate in any house with any kind of heating system, usually in the range of 0.35 to 0.5 ACH depending on your location and climate. That being said-...
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    The first step

    The first step to a successful geo-exchange system is to design the building properly- get the heating and cooling loads down as low as possible to reduce the need to run the geo-exchange loops at...
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    Save more money

    By using the geo system properly- use a water to water geo heat pump and have it supply warm and cool water for the air side fan-coil/heat recovery unit and other heating system elements, and use the...
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    Tinting vs exterior shading

    While tinting can work- the direct solar gain onto the outside surface of the tinted glass can heat stress the glass as well as contribute to increased radiant heat gains to the interior surface of...
  46. Thread: chiller energy

    by gmcd
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    1,137

    Check the run-time hours on each chiller

    And start with the chiller that is used the most, and use some of the above noted advice re: condenser water temperature control. Also check chilled water temperature reset depending on load...
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    R-19 wall isn't R-19

    R-19 insulation in a 2x6 stud exterior wall only results in an overall effective R value of around R-13 to R-14 due to the thermal bridging of the studs, and the top and bottom plates. Unless you...
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    Not necessarily

    With a low level DV system the heat from lights and only part of the heat gains at people level are used to determine the DV air volume required. If the facility is in a humid climate, only that...
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    Low level displacement ventilation

    If you've alredy visited the Swegon website, check out the displacement ventilation design. Low level cool air distributed at the "people level" and high level exhaust to remove the heat from the...
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    The other side of the coin is...

    Garbage in=garbage out. Any kind of calculation is only as accurate as the input numbers. The more accurate the input numbers are, the more reliable and accurate the output numbers will be. That...
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