[J22]

Hi all,
I am processing at material submittal for a pressurization unit for a 42 story tower in the middle east. The system is not hooked up with district cooling and we have our own chillers condenser heat echanges etc.

We have 3 circuits all of different pressures. High zone, low zone and chiller circuit. The contractor submitted a pressurisation unit consisting of only one pump set and 3 pressure vessels with the pressure in each circuit adjusted by control valves and the single pump set.

My question is; Are there any problems that may occur using the above system or would we be better off using 3 individual pressurisation units (each complete with its own pump selection based on the applied pressure) for each circuit.

[caibuadday]

Hi all,
I am processing at material submittal for a pressurization unit for a 42 story tower in the middle east. The system is not hooked up with district cooling and we have our own chillers condenser heat echanges ect.

We have 3 circuits all of different pressures. High zone, low zone and chiller circuit. The contractor submitted a pressurisation unit consisting of only one pump set and 3 pressure vessels with the pressure in each circuit adjusted by control valves and the single pump set.

My question is; Are there any problems that may occur using the above system or would we be better off using 3 individual pressurisation units (each complete with its own pump selection based on the applied pressure) for each circuit.

Why do you have so many zones, 1 pump with PRVs and an expansion tank would be fine
A 42 st building, assumed each fl is 3.5 m height, would required at least 17 atmosphere (250 psia); check the spec on your valves and coils, may not even need the prv

[EGrant]

It would be wise to install a fail over pump unit (N+1)for break down or maintenance.Are all your circuits capable of taking the pressure referred to above or are the zoned circuts banded to the pressure of each circuit.