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  1. Thread: Direct fired

    by drrtu
    Replies
    7
    Views
    897

    I would use, Z83.4 - CO less than 5.0 ppm, NO2...

    I would use, Z83.4 - CO less than 5.0 ppm, NO2 less than 0.5 ppm, and CO2 less than 4,000 ppm & Z83.18 - CO less than 25 ppm, NO2 less than 3 ppm, and CO2 less than 5,000 ppm based upon review of...
  2. Thread: Direct fired

    by drrtu
    Replies
    7
    Views
    897

    The limits will depend on the application. Try...

    The limits will depend on the application. Try http://www.absolutaire.com/eng_resources.vml they have a few docs publiished.
  3. Thread: Direct fired

    by drrtu
    Replies
    7
    Views
    897

    The major ones are: ANSI Standard Z83.4,...

    The major ones are:
    ANSI Standard Z83.4, Non-Recirculating Direct Gas-Fired Industrial Air Heaters. ANSI Standard Z83.4 is the primary equipment standard for 100-percent outside-air direct gas-fired...
  4. Replies
    8
    Views
    1,360

    If the system is VAV not VVT, then your box...

    If the system is VAV not VVT, then your box selection should be correct. Most designers look at a velocity to the terminal at 1500 to 1800fpm. I would say the box /inlet size is correct for the flow....
  5. Replies
    8
    Views
    1,571

    Rapid and Weather-Rite are the same company with...

    Rapid and Weather-Rite are the same company with similar products. Both were acquired by Roberts-Gordon. Look at the Rapid 2000 vs. Weather-Rite XT.
  6. Replies
    4
    Views
    1,005

    Automotive antifreeze products typically contain...

    Automotive antifreeze products typically contain silicate-based corrosion inhibitors. These fluid & inhibitors have been designed protect aluminum. In a boiler /chiller systems, flow tends to be less...
  7. Replies
    8
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    1,571

    Most of my work is D/B and I like to use...

    Most of my work is D/B and I like to use Engineered Air. The products are an excellent value and the product line is very wide. I have applied both 80/20 units and indirect fired air rotation....
  8. Thread: Helium?

    by drrtu
    Replies
    9
    Views
    966

    Helium is an excellent leak detection means. It...

    Helium is an excellent leak detection means. It will not react with the materials we normally see based upon normal HVAC operating pressures and temperatures. The cost of the testing equipment is the...
  9. Replies
    17
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    2,736

    Why do you want to run the economizer on space...

    Why do you want to run the economizer on space pressure? It sounds like you are trying to fix a poor design by cutting off economizer operation. Depending on the size of the RTU, an accessory power...
  10. Stratification is your friend not your enemy in...

    Stratification is your friend not your enemy in UFAD you need a high RAT. In my current UFAD, I designed two evaporated cooled VAV rooftops at 220 tons each (53 F LAT) that feed 16 12,000 cfm air...
  11. Carnak, I agree with the numbers you have...

    Carnak, I agree with the numbers you have presented on ongthiamguan's design. I would push for a non-bypass design (low LAT). I prefer a VAV system connected to air columns to do the mixing for the...
  12. Yes I did sir. I am starting the commissioning of...

    Yes I did sir. I am starting the commissioning of my 120,000 sq/ft under floor system this month.
  13. Start working with the floor designer very early...

    Start working with the floor designer very early in this project. I have never seen a raised stadium floor design. I would be concerned about elevation changes and the effect of the lower mixing zone...
  14. Replies
    25
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    3,815

    I agree with others, side wall venting is allowed...

    I agree with others, side wall venting is allowed in when working to Cook County. Please tell us the page / paragraph that you are quoting. Did you have an inspector that was enforcing his own...
  15. Replies
    15
    Views
    2,573

    I have a complete unit that I took out of sevice...

    I have a complete unit that I took out of sevice 5 years ago that you can have at cheap price Model # BU067A-ASM Serial # 358896-001 460v 3 phase. Outdoor Unit = Model # CSF083LZ Serial # 98070604...
  16. Thread: Sub-meter

    by drrtu
    Replies
    14
    Views
    1,453

    Opcarriage, send me an email (address in public...

    Opcarriage, send me an email (address in public profile) to discuss local installatations.
    Steve
  17. Replies
    12
    Views
    832

    Hire a consulting engineer to develop a complete...

    Hire a consulting engineer to develop a complete permitable plan. This way you control the work scope and pricing. The engineer will specify the tonnage. A good consultant will give you ball park...
  18. Replies
    4
    Views
    574

    Check with the AHJ re: which local code /...

    Check with the AHJ re: which local code / standard the municipality works to. Outside Chicago we have a lot still working to 2001. I just turned in a permit and the village had us working to IMC...
  19. Replies
    20
    Views
    1,955

    Is each twin being controlled via each microTech...

    Is each twin being controlled via each microTech without an automation system? Just to make sure, are the wait and step times the same between the hunting and non-hunting return fans? Is the return...
  20. Replies
    27
    Views
    2,336

    Bby From your last post, it sound like a...

    Bby
    From your last post, it sound like a simplity setting not the ems.
  21. Replies
    27
    Views
    2,336

    The service company should send a tech with a...

    The service company should send a tech with a pocket pc or a pc with the simplicity software. All new York RTUs have the simplicity board. The blinking light is the simplicity board status. The...
  22. Replies
    13
    Views
    916

    Flyrfan I have seen numerous failures of light...

    Flyrfan
    I have seen numerous failures of light commercial systems that would log oil due to hot gas at the ACCU. The systems were not set up correctly or they tried to HG a large % of capacity. I at...
  23. Replies
    13
    Views
    916

    I agree, add a Rawal at the accu and only use TXV...

    I agree, add a Rawal at the accu and only use TXV at the coil. Talk to Richard Rawal his dad came up with the device. HGBP will cook the pump. If you want HGBP route it to the distributor to false...
  24. Replies
    15
    Views
    1,224

    Nailor make a wide range of OR grilles....

    Nailor make a wide range of OR grilles. http://www.nailor.com/onlinecatalogs/HospitalCleanRoom/HCRDCAT.pdf
  25. Replies
    13
    Views
    916

    I did a linear optical scale manufacture...

    I did a linear optical scale manufacture calibration room and they were also very cheap. The room was 20’x30 all interior walls in a conditioned warehouse. Internal loads inside the space did not...
  26. Replies
    15
    Views
    1,224

    At low flows based upon neck size, the perf will...

    At low flows based upon neck size, the perf will have a better cowanda effect than the throw of a louvered face of the same size. At the other end of flow (top end), the louvered face should throw...
  27. Replies
    7
    Views
    1,103

    Keep the design simple and the pressure, supply...

    Keep the design simple and the pressure, supply and exhaust relationships will work themselves out. First focus on meeting all air in (ventilation) first. Design to the applicable codes / standards...
  28. Replies
    10
    Views
    997

    Use a floor standing unit from Mitsu, Sanyo or LG...

    Use a floor standing unit from Mitsu, Sanyo or LG mounted high on the wall or use a 2 zone system with 2 larger wall mount units side by side on one ACCU....
  29. Replies
    15
    Views
    1,224

    Laminar flow diffusers used in an ER and clean...

    Laminar flow diffusers used in an ER and clean spaces applications have perforated faces. The perforated face allows a smooth stream of clean air down to the table without picking up secondary room...
  30. Replies
    11
    Views
    1,003

    I would check load on an hour by hour basis...

    I would check load on an hour by hour basis showing which component is changing. It sounds as if you have the space configured for zero outside air during unoccupied mode. Change the schedule to 24...
  31. Replies
    18
    Views
    1,213

    If you are in Chicago, Trane in Willowbrook can...

    If you are in Chicago, Trane in Willowbrook can help you with this. We have done numerous twinned units with and without Trane automation. Make sure both MP supply motorized isolation dampers are...
  32. Replies
    12
    Views
    1,025

    I had bid a LEED project that was a senior center...

    I had bid a LEED project that was a senior center that used http://www.islandaire.com
    PTAC units with hydronic coils and 90% boilers. They may build a unit with 407c.
  33. Replies
    4
    Views
    507

    You did not tell us if the space will be...

    You did not tell us if the space will be multi-story or single. Your design basis of two units, leads me to believe me you are leaning towards a VAV design. At 28’ and a single story, I would prefer...
  34. Replies
    3
    Views
    578

    Check with a local control contractor. He should...

    Check with a local control contractor. He should inspect the equipment and review your needs. Expect to pay him for his techs. time. Talk to the installing mechanical contractor if they install web...
  35. Replies
    8
    Views
    733

    Wouldn’t an oversized ACCU cause the unit to go...

    Wouldn’t an oversized ACCU cause the unit to go off on the low evaporator trip? You must have had some very strange condenser fan settings for the unit not to build head. I have seen the control...
  36. Replies
    5
    Views
    1,186

    You need to find the actual load on the x-former....

    You need to find the actual load on the x-former. Have the EC measure the primaries. Then using a submittal or catalog data sheet find the efficiency. Do not use the nameplate you will have too high...
  37. Thread: Noise issue

    by drrtu
    Replies
    14
    Views
    1,270

    We had a few odd noise issues with the 12 ˝ and...

    We had a few odd noise issues with the 12 ˝ and 15 ton voyager CV gas / electric units. The sound was the fan and compressor flexing the base of the machine. The noise was very loud directly below...
  38. Replies
    2
    Views
    1,266

    Do the spandrel as a wall not as a window.

    Do the spandrel as a wall not as a window.
  39. Thread: Busy week

    by drrtu
    Replies
    14
    Views
    2,617

    Insulation Plus is a retailer...

    Insulation Plus is a retailer http://www.milwaukeeinsulation.com/contactus.htm I have been buying roll insulation, pins, glue, sleeve and flex from them. They had good prices on sheet steel for a few...
  40. Thread: Busy week

    by drrtu
    Replies
    14
    Views
    2,617

    Just checking on the OA. The wrap looks good. We...

    Just checking on the OA. The wrap looks good. We sleeve the round duct ourselves and sub the square duct. Insulation plus has good pricing on sleeve & flex.
  41. Thread: Busy week

    by drrtu
    Replies
    14
    Views
    2,617

    Did you wrap the duct or sub it out? How about an...

    Did you wrap the duct or sub it out? How about an economizer or manual damper / hood on the RTU. I did the Marriott courtyard a few blocks away.
  42. Replies
    11
    Views
    2,522

    Try Industrial air systems, Engineered Air,...

    Try Industrial air systems, Engineered Air, Applied or Rapid. Lately, I have used more Eng. Air units. Stick to the 2 fan units, no extensions, high/low/off burner, SS primary and secondary heat...
  43. Replies
    8
    Views
    1,165

    Try changing the belts. Matched set?

    Try changing the belts. Matched set?
  44. Thread: Trane CTI

    by drrtu
    Replies
    4
    Views
    810

    The bigger question is how do you get a precedent...

    The bigger question is how do you get a precedent to run on 100% OA, even with an ERV you will have a hard time with the latent load. You have a thin DX coil. I would use a leaving air controller...
  45. Replies
    21
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    3,255

    For the first time in the last few years, we are...

    For the first time in the last few years, we are very slow now. Service is ok but s/m and piping is slim.
  46. Replies
    21
    Views
    3,255

    This is what we use....

    This is what we use. http://www.durodyne.com/products/Machinery/MODEL_FG-1.pdf
  47. Replies
    21
    Views
    3,255

    The company is O’Hare Engineering. The IMC also...

    The company is O’Hare Engineering. The IMC also forces you into 90.1 and international energy conservation code (IECC). I believe 90.1 is R=6.8 but IECC is R=8 for exposed heating/cooling ducts...
  48. Replies
    4
    Views
    567

    In order to size the unit you need to determine...

    In order to size the unit you need to determine the load. Try a Bard unit. http://www.bardhvac.com/app_cntr_telecomm.shtml
  49. Replies
    21
    Views
    3,255

    Actually canvass connections allow for a little...

    Actually canvass connections allow for a little slop on setting the unit. Most of the time on the old horizontal units we do replace the downturn plenum with new metal. The IECC now requires R-8...
  50. Replies
    21
    Views
    3,255

    It’s a small world. This looks like the building...

    It’s a small world. This looks like the building next to mine. Were you the guy who needed some sheet stock to complete the work? My office is 55 Messner drive. Why did you cross brake all 4 sides?...
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