Hi,
How do I calculate the pressure loss of a converging bullhead tee in a return duct system. The tee has dimensions 23"x23" for the main duct and the branch. Thank you!
HerrKaLeun,
Thank you for the question! I have a supply duct in the plenum, not sure if there would be any electrical conduits. Most of the plenum height is 2’, there is only one room above which the plenum height is 1’.
Drazen,
When I calculate the PD through the plenum with concrete walls, can I use the same pressure loss chart for metal duct? Where do I get a chart for concrete wall duct?
Hi,
I would like to calculate the return air pressure drop through a plenum between the first and second floor of a building. The building 1st and 2nd floors shear common plenum return. Do I have to take into account the pressure drop of every single return grill on the ceiling of the first...
Thank you everyone for your help! I am sorry I should’ve clarified that I am using WSHP to condition the room. The WSHP is connected to a closed loop cooling system. The cooling system is designed to carry heat away from the electrical equipment. That energy can be utilized to heat the space...
The design temperatures are 72F and 76F for heating and cooling respectively respectively. Not familiar with heat rejection system. There is a cooling system in the equipment rooms that utilizes a water as cooling fluid.
Hi,
I am designing a HVAC system for an equipment room that houses a large electrical apparatus. The load in the room can vary from 10,000Btu/h to 85000Btu/h. The room area is 1345ft^2. Should I use CAV or VAV box?
Thank you willard3!
I was not sure if 1% means that the design temperature has been exceeded only 1% of the time during the year or the design temperature occurs only 1% of the time during the year. However, I think that my first assumption is correct. Please let me know if I am wrong. Thanks!
Drazen,
In the equipment room there are two large electric units: pulse generator and AC/DC power supply. The equipment does not produce any air pollution. Equipment maintenance would be performed semiannually. Yes, the door can be open to the adjacent conditioned space.
Hi Everyone,
I have to condition a space which would be classified as non-occupant area. WSHP will be used for cooling and heating of that area. Do I have to provide an outside air for a space that will not be occupied at all? Equipment in the space requires conditioning of the area. Thank you!
DRWeig and Drazen,
Thank you for your help!
Drazen,
Regarding question 1 response, you said that the minimum pressure is not equal to the static head. How do you determine the system minimum pressure?
I agree with DRWeig answer that elevation and air relief valve minimum closing pressure...
Hi,
Can someone help me with the following questions?
1.Is the minimum system pressure equal to the system static head (elevation)?
2.Does the system expansion tank precharge pressure have to equal the system minimum pressure?
3.Is it better and more conservative if the expansion tank...