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Recent content by imok2

  1. imok2

    CFMS vs Tons

    To repeat a previous answer: If 400 cfm of air and a delta T of 20 degrees is achieved, this is equal to only 400X20X1.08=8640 btu/h. However, this neglects the latent heat portion of the cooling load.
  2. imok2

    air side economizer

    mauricestoker Because I was a Refrigeration Fitter and worked in many areas of this industry doing construction and service I saw a lot of equipment that wasn't maintained properly because it was the first thing people did was cut the maintenance budget and when they got the repair costs they...
  3. imok2

    air side economizer

    If you’re not prepared to spend money on a proper maintenance then you’re probably wasting your time because estimates indicate that only about one in four economizers works properly, with the remaining three provid¬ing sub-par performance or, worse yet, wasting prodigious amounts of energy...
  4. imok2

    Turning cooler off in old auditorium when not in use damage anything?

    Your system seems to need some serious inspection so if your not willing to spend some money for an up grade then I would shut it down when not in use and do a calculation on energy savings and maybe you can save enough to improve the system also I would be curious to see how it would effect the...
  5. imok2

    Glycol water coil - GPM calc?

    Correction Go to www.engineeringtoolbox.com/ Ethylene glycol
  6. imok2

    Glycol water coil - GPM calc?

    Go to www.engineeringtoolbox.com/erthyleneglycol
  7. imok2

    Solution for existing undersized return air duct

    If the econimizer is working then that makes your present ducting even worse because my sizing was based on 1900 cfm supply and 2000 cfm return and if the ducting was based on deminished supply and return then why have an econimizer that is defective? I would think that you would repair the...
  8. imok2

    Solution for existing undersized return air duct

    Well your ducts are definately undersized I would recommend replaceing them with this: For a friction rate of 0.1 /100 ft your supply should be 14” x 20” and your return should be 14” x 24” for a supply velocity of ~1000ft/min. and a return of~850ft/min. Your A/C is not very efficienr and...
  9. imok2

    Open Refrigeration Fixtures in Supermarkets

    I believe he answered his own question "where they obviously create cooling load"
  10. imok2

    ceiling return

    Yes
  11. imok2

    HVAC JOB

    My advice is to find an HVACR Contracor eswho does service and constuction and inform him of your limatations and possible land a job as a learning application engineer and also take some classes on line in various service and contructions. While exposing your self to the service and...
  12. imok2

    ceiling return plenum static pressure?

    xpsboy At 80% opening for a 24"x24" the CFM would be about 2240 and the velocity would be about 700 FPM maxium to maintain an acceptible presure drop.
  13. imok2

    Suction line accumulator vs. pump-down w/ hard start kit

    I would install an accumulator becaus of its simplicity.Flood back can occur when the ASHP is reversed, such as the defrost mode, or when the compressor is subject to low ambient temperatures. Accumulators are typically installed in the “true suction line” upstream of the suction port of the...
  14. imok2

    HAP 4.41 Heat Loss/ Heat Gain Calculations.

    A rule of thumb in air conditioning work is that 400 cfm of air is equal to 1 ton. If 400 cfm of air and a delta T of 20 degrees is achieved, this is equal to only 400X20X1.08=8640 btu/h. However, this neglects the latent heat portion of the cooling load. The latent heat (3360 btu/hr) is...
  15. imok2

    Evaporator Coil

    I believe your centergrade should be farenhight because 50* C = 122*F and 28*C = 82.4*F that's not very cool drinking water?

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