1. ## Member forum?

Hi I am new to the site and was wondering if there is a thread for introductions? I was going to introduce myself and provide a little of my background and experience. I'm a newer licensed refrigeration tech and was looking for a good forum to share and also converse with other techs about past and present projects. I had a look on the main board but didn't see any. let me know if I missed anything! Thanks

2. Well you found the right site. Look into the Pro Membership and welcome aboard.

3. Thanks VTP99 when I get the 15 posts I will apply for that pro section. I already have an engineering question lol

4. I'm no engineer but that doesn't stop me
Is it for refrigeration or comfort cooling/hearing ?

5. Comfort cooling, I want to do my first design of supply plenum so I am researching manual D. I have lots of experience on the install and service end of A/C but I really didnt learn much when it comes to duct design or airflow design. Was looking to do a small system with about 9 supply diffusers. I did a sizing calculation and was sure to figure for additional loads from windows. The IDAHU supplies 900 cfm @ .3 in wc on the low setting. I was going to design off of .1 WC and calculations are for 4 air exchanges per hour. I managed to split up my CFM per room across 9 diffusers. The problem I am working on is how to maintain my velocity to each diffuser branched off of the supply trunk. I was thinking initially 14" round for my main duct. I know theres going to be the need for reducing the diameter of the trunk to achieve this. So to put it simply I was looking for help with the math. Or if you know of a calculator tool or any othere resource I can look at. Thanks

6. After each 1 or 2 supply duct branches reduce the trunk size to account for the new cfm total. So after 2 branches reduce to 12in. The 3 more and drop to 10in. It depends on the location or the branches and their length also. Draw us a diagram of the building and layout the system.

7. thanks, the more I am reading on this it seems a good choice would be to do the manual j,s,d from start to finish but it seems like alot of work. almost more pitched at new construction.

8. We closed the Welcome forum because new members used it for a dumping ground of questions instead of using the forum categories.

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