cfm

[orland25]

hi friends; How many cfm I need for 20x14 room,Iam talking about cfm, not cooling. THANKS

[Carnak]

The amount of sensible cooling needed and a temperature differential between what you want to maintain the room at and the temperature of the supply air to the room tell you the required CFM.

Are you refering to outside air required for this 20x14 room, to provide ventilation?

[paulj]

280, rule of thumb is 1 cfm per sq. foot.
But thumbs are meant to bend

[hvacpope]

for ventilation purposes 15cfm per full time occupant is the rule for most of the country.

[orland25]

Ok;FRIENDS Now we have a new small room 24x14.But another side of the wall i have a clean room,the problem is in the small room and the clean room they have hepa filter with fan all hepa filter have a fan. We do 2 hole in tha wall and I put 2 fan, one fan supply and other fan return.But does not work,the air is taken of the plenum of the clean room.The question is I should connect to the pricipal duck. THANK

[john dalton]

Dear Orland25,

Hold on cowboy……….lets stop this train before it wrecks.

First of all your original question doesn’t supply nearly enough information for anyone to answer it with any degree of accuracy. We can’t answer a normal HVAC project with a “rule of thumb”, bent or otherwise, yet alone one that involves HEPA filtration and a clean room.

Second of all, you DO NOT add fans to draw the air out of a clean room and then add other fans to return the air back into the clean room because of several reasons, such as, fans are a source of contamination themselves in clean rooms, your cross contaminating the original clean room with this second room, regardless if it’s a clean room or not, and your more than likely adversely affecting the positive pressure of either rooms, clean rooms or not.

In order to get accurate and detailed information from this or any forum means you need to first supply accurate and detailed information so we here can use it to formulate our own ideas and suggestions, and then give you direction on this or any project.

Looking forward to your next post…………………

Respectfully Submitted,
John J. Dalton

[Carnak]

Yes more information is needed. The smaller room almost sounds like a big air lock.

[orland25]

hi friends; Ok I have (28air shot)in the plenum of the clean room,and 400cfm per shot)this is varible because the VFD in the unit play with the HZ. Okay in the clean room the temp is 70deg, humidity 48. That this all well,no problem. Okay remember the small room 24x14 I need the same one specification 70deg and 48 to 50 hum)If Iam goin to put 3 or 4 airshot inside of the small room which seriuos the measure of the duct the I need,and cfm. (remember under shots they are the hepa filter with one fan each one. These they collect the air to send to the small room. THANK ALL

[hvacpope]

orland25, You are setting yourself up,pretty soon some of the wise guys here are going to start making a clown out of you, I can't understand anything you wrotte so far, and I dont think that anyone else can,Maybe you should first find a bi-lengual friend to help you with the translation.OK

[Carnak]

Then you need to know the sensible load of the room and the supply air temperature to calculate your CFM.

Need to know the latent load to maintain the RH

[Edited by Carnak on 04-13-2005 at 09:21 PM]

[orland25]

if you do not undestand,please close the mouth. pongase a estudiar un poco mas.GRACIAS

[drivewizard]

Do they have Engineers in your part of the world, or is this another "Hack" job.
Were you low bid by chance?

[Carnak]

Originally posted by orland25
if you do not undestand,please close the mouth. pongase a estudiar un poco mas.GRACIAS


Uckfay Offay

[ironhorse]

Tu madre chupa huevos de caballos, pendejo.

[jrbenny]

Originally posted by Carnak

Originally posted by orland25
if you do not undestand,please close the mouth. pongase a estudiar un poco mas.GRACIAS


Uckfay Offay










Thanks, I needed a good laugh.

[Dowadudda]

Great. Yet another place where no one speaks english. :D

John J. Dalton. You better mind him. He sounds like the guy I need to get to know.

[john dalton]

Dear Dowadudda,

Your last comment wasn’t entirely correct, English still spoken here friend. And God willing, spoken all over the world forever. God bless America!

Respectfully Submitted,
John J. Dalton

PS: God has already blessed America beyond its wildest dreams, NOW its time for America to bless God.

[john dalton]

Dear Orland25,

First and foremost, I’d like to apologize for comments made to you from my colleagues at this forum based upon your lack of command of the English language. The purpose of this forum, and these individual threads, is to share the vast wealth of HVAC knowledge, experience, and options that has taken its participants hundreds of thousands of hours to accumulate.

To that end, I will give you my honest comments regarding the above referenced clean room project with no additional comments concerning your English skills. My original posted comment to you was to ask for addition information regarding your project so we here can “formulate our own ideas and suggestions”

Based upon the information you’ve given us here at this thread, it’s my option that the complexity of this HVAC modification will require either an HVAC engineer or contractor who specializes in clean room environments to be completed efficiently, correctly, safely, and with the minimal amount of downtime to the existing clean room.

The above comment was not based upon your lack of the English language, but was based upon your lack of apparent design and operational knowledge of basic clean room principals.

Respectfully Submitted,
John J. Dalton