Hi Lim & Vincent,
Here is my finding for the DC walkthrough, for any questions please let me know.
· Supply airflow may or may not be sufficient. My experience to the top supply airflow velocity is around 9m/s, so the total airflow for one supply air vent is 6m/s * 3.14 * 0.3*0.3 * 3600 =around 6000CMH, which gives around 23KW cooling capacity for each vents….times the total supply vents found in the room, I can estimate the total supply air to the room can only cool is no more than 100KW IT load. 2 things can to do solve this supply shortage problem.
a. Find the supply air duct inside the return plenum and open more supply vents on top of the cold aisle.
b. Buy new CRAC
· No blanking panel inside the cabinet
· Airflow leakage inside the cabinet thru the gap between mounting rail and side panels.
· On the site, didn’t find any hot air return vent. That means the only way for the hot air leaving the room is the door. couple of things CAT might consider to solve this problem
a. Find the return duct inside the return plenum and open up the return vents on top of hot aisle and duct these return vents to the return duct, or
b. Use the complete return plenum for hot air. Install the exhaust fans on top of hot aisle and suck the hot air into the return plenum. And then on the perimeter side of the room use the fans to push the hot air leaving this DC area to the office area. They also need to consider to have a good seal on the ceiling so that no hot air can leakage from the plenum into the room
· Use some simple material to seal up the hot/cold aisle. Some plastic air wall might do the job.
· Notice there is one cabinet without the side panel with 2 switches inside the cabinet and the hot air directly blow into the front. Please put the side panel on and have a return vents on top of the cabinet might solve the problem.
How to do it?
· One step at one time, do it slowly. Do one thing and then wait for the airflow balance inside the room(normally takes half day) and then do the next one.
· Follow the below step
a. blanking panel first
b. seal gaps inside the cabinet
c. seal up the hot/cold aisle
d. return vents on the hot aisle