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Recent content by BM4BRANES

  1. BM4BRANES

    Return air ducts in wall cavity

    Consider lining the cavity with this. http://www.certainteed.com/products/insulation/hvac-mechanical/317382
  2. BM4BRANES

    Pneumatic valve operation

    I doubt the valve is spring return, one signal opens and the other drives the valve closed. 2 positive positions, right?
  3. BM4BRANES

    Can one ref-compressor unit be used to have 2 independent temperatures

    valve mgf's all make evap pressure regulators(EPR).An epr on the warmer coil will do the job but you'll need an unloading compressor to manage part load conditions. The key concept missed is redundancy. Putting all the eggs in one basket will be a huge blunder! saving a few dollars up front...
  4. BM4BRANES

    Room temperature flucation problems

    I think it could be safely stated that a perforated t-bar supply that is properly sized will out perform a linear slotted diffuser in term of flow pattern, maybe not noise. You made no mention as to velocities, windows, or proximity. Return air location matters a lot, where is it in relation to...
  5. BM4BRANES

    Outside CHW pipe rusts when system is drained during winter

    Bron, I've assumed there is a closed loop corrosion inhibitor (nitrite)when filled, yes? If the corrosion occurs during wet periods, you may be doing all the right things for all the wrong reasons. BM
  6. BM4BRANES

    Outside CHW pipe rusts when system is drained during winter

    I would not spend any time on a vacuum, the volume to squeezed is enormus and coupled with the dehydration of any residual water, well, it would be summer if it got done at all.A simple complete purge with under no pressure ought to accomplish the task. You will need to incapacitate the air...
  7. BM4BRANES

    Outside CHW pipe rusts when system is drained during winter

    I too like the N2 purge idea, why are you apprehensive?
  8. BM4BRANES

    Hydronic vs Electric Baseboards

    If you are willing to spend money with an emphisis on payback and continue to heat with resistive, why not spend on solar panels. Providing you have good exposure, tax advantages would make the financials a no brainer, yes?
  9. BM4BRANES

    Thermal VAV versus Powered VAV

    Are you refering to "thermofuser", vs a conventional vav box? Vav boxes are almost always found in buildings with other vav boxes and work reliably well. Thermofusers are used on small contant volume package units with trouble spots where the area of trouble differs from the area near the...
  10. BM4BRANES

    R22 Geo Heat Pump

    A qualified company/ tech should have no problem sizing up your situation, if or what problems exist and what your options are.It's a little rare to find compressors above 5 tons on single phase power. I do find the efficiency comment interesting. Ground source Heatpumps are widely accepted as...
  11. BM4BRANES

    DUCTINGS LOSSES

    From a simple/practicle approach, what is the rated capacity of the A/H,how big is the area served?The hood measurements would be more difficult to goof up, agreed? what is/was your objective originally? How critical is the project?
  12. BM4BRANES

    Air "Pusher"?

    At risk of stating the obvious, we should assume that the convention heat sink methodoligy found in the electronis field is no practicle. If you had a constant source of clean dry air from a local compressor, you could diplace the heat while avoiding the maintenance/dust /fan failures issues...
  13. BM4BRANES

    filling up closed water loop

    Open tanks(without bladder) are no longer common. MUW connections are usually found on the tank connection line. Bladders are charged with 2/3 to 3/3 of static fill pressure prior to system fill. Fill pressure is usually 12 to 15 psi at highest point.
  14. BM4BRANES

    Bleed off from Cooling tower

    Uh oh, sounds like the immediate problem is scale build up. Installing a bleed valve now will not undo years of differed maintenance. After you have resolved the scale(heat transfer) problem, or installed a new tower, a bleed valve needs to be installed. Once you establish the Cycles of...
  15. BM4BRANES

    coil freezing

    Hot gas bypass would be the preferred method to manage part load conditions for vav type applications rather than on/off controls. HGBP will cost more up front but will not beat a compressor to death prematurely like the freeze stat method.

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