Hi....

I am doing a 6 storied building project for which i need to determine the head required for the pressurisation units. THe CHW pumps and heat exchanger are located at the basement and the chilled water is provided from District Cooling Plant at 16 deg F delta-T.

How can i determine the head required for the pressurisation unit pumps.

Can anybody help me out please......!!!

reagrds,
Anoop.

caibuadday

6 stories, how height?.......... 10 ft === 4.33 psig.... add the pressure lost of the coil (hieghtest 1), its horizontal piping ( fittings), and the head press and throw in about 10 lb; that your min press..this sound like a HW question................

apv

Mr.Caibuadday,

Thank you very much for your reply.
The floor to floor height is 3.5m and the pump room is in the 1st basement. I have already selected a pressurisation pump set with a head of 50 ft. This was based on a chiller system design with chillers and pumps at roof. Now it is changed to a DCP and hence all the pumps are relocated to the basement floor. now, the supplier for the unit claims that this 50 ft will not be enough to support the present condition which i couldnt understand why........

regards,
Anoop.

caibuadday

assume your slab is 25 cm thick, each floor total 3.75 m, at 6 stories the head is about 75 ft =32.5 psig, you need atleast 54 psig to get the equivalent of the (50ft) chiller on the roof. At 50 ft from the basement only push the water to third floor