Heating, Air Conditioning, Fridge, HVAC/HVAC


my question is concerning a commercial office space and low flow air, it is a roof mount commercial air conditioner servicing approximately 50 office spaces, One office space in particular gets very low airflow while all of the other offices around it are fine. All of the VAV's are working properly and I am new to this building from what I'm told this problem has been going on for the last 15 years and no one can seem to figure it out. after looking at it I determined there was too much flex duct being used, Way too much friction, too many 90 throat elbows. i'm just trying to get some other opinions on something else it could possibly be. The rooftop A/C unit is approximately 35 to 40 years old. my thinking is other than the crappy ductwork I think that maybe the office space is getting the most it's ever going to get, and that's why it's been an issue for the last 15 years that perhaps it's not the AC that is the problem but maybe should be focusing efforts on increasing the airflow to the office space manually somehow. Anything you could add to the mix would be appreciated. Thanks.

you need to get the test equipment out.

Temperature of return air.  Temp of supply air.  Pressure in the main supply ducts to offices which operate well, and the one with problems.  Pressure in the ductwork after the vav boxes.  Get this info., and more and compare it to industry norms, and areas in the same building which work well.  

Ductwork design is an issue, however if you have pressure at one point, and none at another point in the same duct there is something in the way, like dampers and fire dampers.

The other thing is building construction and orientation to the sun.

Happy Hunting!

Heating, Air Conditioning, Fridge, HVAC

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Mike Reavis


Questions related to "Wet Heat". This is heating your home, office etc. with radiators, panels, and convector apparatus. Steam and water heat. I can answer questions about boilers, piping,and associated parts of these systems. Please do not ask for specific information about how I feel about one boiler, etc. over another--These questions should be directed to a licensed contractor that you know of, or that your neighbors and colleagues look to to provide solutions.


I have 20 plus years experience, which has lead to passing my state master HVAC license.


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I work on the manufacturer's side of the business currently

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