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air change
2

air change

air change

(OP)
how to calculate the air change of the area? like warehouse?

RE: air change

Do you need to move all the air volume?
Peak of the building to floor and all walls sides?

Height x Width x depth of length? in cubic ft or meters?

Or just cooling air changes of the top 8 ft high or less for open - top offices and manufacturing and retail, etc, not trying to cool all of the air space to the ceiling...?

RE: air change

(OP)
just cooling air change for loading bay warehouse!

RE: air change

depends on the requirements. How warm can it get? what is ambient design temp? internal loads, solar load etc?

just ventilating won't cool it much unless you have much internal heat geenration. If it is 100°f outside, bringing in air won't make it colder than 100°F

RE: air change

Hire an Engineer who knows how to do this and don't try to bootstrap.

RE: air change

Please, save yourself some money and DON'T hire an engineer to answer you question:

Air changes per hour (ACH) = (cfm * 60) / room volume.

Room volume is area times ceiling height.

Airflow is in cubic feet per minute times 60 minutes per hour. Divided by the room volume in cubic feet. It's a unitless number.

For cfm, you use the higher of supply or exhaust.

RE: air change

You know, if he can't figure this out before he asks the question, he needs an Engineer...


Not rocket science

RE: air change

he may wanted to know how to determine how much he will need?

anyway, would be good what the question is for, a design?

RE: air change

Gents, the question was how to calculate an air exchange rate, nothing more. Simple math not requiring an engineer. If there is an application that made the situation more complex, maybe there would be more to discuss.

RE: air change

I wouldn't like to complicate it if not really necessary, but something is screaming at me...

The phrase "cooling air chance" carries little sense by itself but if we assume that question is posted by person not familiar with basice, I would assume that Mr. needs to calculate supply air flow needed for cooling the space...

chas, your intentions are undoubtedly good, but giving hand to someone who possibly doesn't know where he is going toward is unlikely to give satisfactory results, sometimes it's more pressing to determine whether he is going to abyss.

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