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ADDIN COOLING POWER TO A EXISTENT SYSTEM

ADDIN COOLING POWER TO A EXISTENT SYSTEM

ADDIN COOLING POWER TO A EXISTENT SYSTEM

(OP)

Hi all.

I had 3 (8,5 and 4 floor)  buildings with water chiller ,used for VAC 8 °C leaving water 13 °C return.

First a 100 TR on a roof of the 8 floor building to supply to the lowers floor.

A 40 Tr and 20 TR in parallel  at the roof of the 4 floor building.

And one 200 TR on the 5 floor roof to help the other two and for futre use and ampliation on the 3 biuldg.

QUESTION.

In wich way should I do the interconection so it can became a whole system?

The 100TR and 40+20TR  have its pump , manifolds , etc.

After the system is runing, a control system to run and start each chiller acording the demand.

The system is for a Hospital , so some parts of it need cooling all year round.
Thanks in advance.


  







Pardal

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

Pardal,
how is the configuration in each building? two loops (consumers in one, chillers in the other) and all constant flow? Perhaps with more information someone could help you in this task

rgs

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

(OP)
Hi absmex, thanks for you tips.
You are rigth    
Following details:
100 tr chiller    
roof top 8 floor    chiller 100 tr
floor 8    one pumP to chiller on return from all floor.
floor 8    one pump to donward floors
floor 7    no use now , to be used next spring setp 04
Floor 6    idem 7
floor 5    idem 7
floor 4    14 fan coil 2 Way on-off valve; 2 gral area: 2 ahu  2 on-off way valve for all units.
floor 3    12 fancoil 2 on-off way valves; One common area 1 ahu modulating 3 way valve
floor 2    12 fan coil 2 Way on-off valve; 2 gral area: 2 ahu  2 on-off way valve for all units.
floor 1    9 quirofan with modulating 3 way valves; 3 gral area  : 3 ahu with modulating 3 way valves
floor 0    2 ahu with modulating 3 way valves
floor-1    5 ahu with modulating 3 way valves
floor-2    1 ahu with modulating 3 way valves

20 + 40 tr chillers     
roof top 4 floor    two chillers plus two manifold  to diferents circuits
roof 4 to -1     a lot of fancoils and ahu with 2 way on off valves
roof top 4 floor    6 ahu with modulating 3 way valves

    AHU : AIR HANDLING UNITS



Pardal

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

Hi PARDAL!

Let me see:

- A 8 floor building with a 100 TR chiller;
- A 4 floor building with 20 + 40 tr chillers in parallel;
- A 5 floor Building with a 200 TR chiller.

Questions concerning your question:
- Can you confirm that description?
- What is the layout of those three buildings, with the relative distance between each other, and the orientation, in respect to the sun?
- Can you give the inside-configuration of the third building, as well?
- Are those buildings running 24/24 hours at 100% all the time? or not?
- Please, provide further information, you feel it will be necessary for a deeper analysis, in order to try to give some help.
zzzo      
 

      

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

Hi again PARDAL!

A second reading tells me that the 200TR chiller is now  redundante to the other three and it will be used for future ampliations in all the three buildings.
Can you precise/forsee the scope, in percentage, of these ampliations at each building?
zzzo  

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

(OP)
Hi 235zzo.

My concern is only conceptual .

All 3 building where do on the run.

Just now the 20+40 are over demanded.

The 100 TR has ran the last 30.000 hr at a 70% aproximate.
Tomorrow I will have the precise data.
The  200 has ben bougth specting to complte the futura demand.

Please tell me where I can send you a schematic drawing.

Thanks in advance.


 

Pardal

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

Good Morning Pardal

Just a note in meantime, I must give my generic interpretation about your case:

- Even your "concern is conceptual",
- to get a good framing for your question,
- you have to provide detailed data,
- because to apply one or another concept/methodology,
- can also depend on small, particular aspects as well,
- and the interesting thing you just realise, sometimes after the first studies/tries/implementations.
- So the concept view/framing, sometimes changes surprisingly.

I think you quite understand what I mean, being a person (re)searching for new solutions/equipments.
Kind regards.
zzzo
   

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

Hi PARDAL!

I just realized now, I didn't tell you my references:
You can reach me at: rapozzo@clix.pt
Kind regards.
zzzo

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

You have to get a handle on the long term plan of the hospital for expansion so you can size the interconnecting piping for the design ultimate scheme. Locate a main plant that can accomodate the ultimate no. of chillers, including spare for backup if the largest chiller fails & close to possible location of cooling towers (including additional units for future). Consider distributing main plant chilled water at 38°F then having secondary pumping in local buildings, blending water to the current design CHWS temperature in each building. In this manner the size of the main can be smaller. Figure on where to run piping without blocking the planned expansion of the hospital buildings. Provide primary/secondary crossover connection at each building. Convert pumps to VFD & use two way control valves.

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

Oh I forgot to mention: The local chillers remain but the central plant chiller can provide CHWS instead for reliability. Use outdoor air economizer on AHU where possible so chillers can be off in winter. You may have to use 1 location for expansion tank & makeup. Provide manual 3/4" NO line on CHWR across automatic CHWR valve to the main loop for pressure equalization when the control valve is closed.

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

(OP)
lilliput1:
I understand your way , where I cand find more info about it ?

Please explain the following term's meanings

CHWS

CHWR

VFD

Thanks in advance

Pardal

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

CHWS = Chilled Water Supply
CHWR = Chilled Water Return
VFD = Variable Frequency Drive

I suggest you let a professional HVAC Engineer do the design work. You will not want to be liable if the system you design does not work.

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

(OP)
But if I just want to learn a litle more?

Pardal

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

Seek employment in an engineering consulting firm. Start as designer then take HVAC courses offered by ASHRAE or local Engineers Club. You will be getting free trade magazine subscriptions or you can request them if they know you are in the business. Once in, look at work the firm has done & learn from them. Understand the principles & use common sense.

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

(OP)
What about I'm not in USA.?

Pardal

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

You do have consulting enginering firms in your country don't you? ASHRAE is a world wide organization.

RE: ADDIN COOLING POWER TO A EXISTENT SYSTEM

(OP)
Not I have not.

All the project and work was done by a "I do not why do it, engineer"

And I shall to resolve all the bad done work.

You never wonder how the comercial relation are done in my country.

There is a tale about it:
By the 70 one say
There are 4 economyc and politc way to do things.

The Capitalist,

The comunist.

The japan Way

And my country way.

The first 3 as a razon to be,  and undertood.

My country way, has not  and will not  have any reazonable way to explain it.

Hope you understand me.








Pardal

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