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Jacek
08-01-2012, 10:01 PM
Hello Mates,

Could someone tell me what the lowest water outlet temperature in a centrifugal chiller is?

install monkey
08-01-2012, 10:03 PM
what make and model

Jacek
08-01-2012, 10:06 PM
what make and model

Carrier, York, Trane...

install monkey
08-01-2012, 10:17 PM
depends on the system design/application

Jacek
08-01-2012, 10:19 PM
Just pure water. How low we can cool water down with a R134A centrifugal chiller?

install monkey
08-01-2012, 10:22 PM
carrier 19xr Evaporator 19XR Minimum Maximum
Evaporator entering water temperature* C 6 17
Evaporator leaving water temperature* C 3.3 10
Condenser (water-cooled) 19XR Minimum Maximum
Condenser entering water temperature* C 16 35
Condenser leaving water temperature* C 13.3 44
*
For application requiring brine operation, contact Carrier s.a. for unit selection

goshen
08-01-2012, 10:24 PM
Hi
wouldnt try to go lower than 5 degc/.
good luck

stufus
08-01-2012, 10:28 PM
AS ABOVE :cool:
I wouldn't take untreated water below 4-5c as Ice crystals will start to form ,Which could get messy quickly.
Cheers
Stu

install monkey
08-01-2012, 10:28 PM
york lchmChilled Water Leaving Temperature : R22 & R134a models : 4.0 C 10 C
R 407C models : 6.0 C 10 C
Chilled Glycol Leaving Temperature : R22 & R134a models : - 6 C 10 C
R 407C models : - 2 C 10 C
WATER /
Chilled Liquid Temperature Range through Cooler : 3.3 C 8 C
GLYCOL
Standard Condenser R22 models : 30 C 41 C
SYSTEMS
Liquid Leaving Temperaure : R134a models : 30 C 55 C
R407C models : 30 C 35 C

Jacek
08-01-2012, 10:30 PM
carrier 19xr Evaporator 19XR Minimum Maximum
Evaporator entering water temperature* C 6 17
Evaporator leaving water temperature* C 3.3 10
Condenser (water-cooled) 19XR Minimum Maximum
Condenser entering water temperature* C 16 35
Condenser leaving water temperature* C 13.3 44
*
For application requiring brine operation, contact Carrier s.a. for unit selection


It means that for your example the lowest water temperature is 3,3 deg. C? Is it the limit? Could we go lower? What limits the lowest water temperature? Evaporation temperature? Evaporator construction?

stufus
08-01-2012, 10:31 PM
I still wouldn't run it down below 4-5c
Cheers
Stu

york lchmChilled Water Leaving Temperature : R22 & R134a models : 4.0 C 10 C
R 407C models : 6.0 C 10 C
Chilled Glycol Leaving Temperature : R22 & R134a models : - 6 C 10 C
R 407C models : - 2 C 10 C
WATER /
Chilled Liquid Temperature Range through Cooler : 3.3 C 8 C
GLYCOL
Standard Condenser R22 models : 30 C 41 C
SYSTEMS
Liquid Leaving Temperaure : R134a models : 30 C 55 C
R407C models : 30 C 35 C

stufus
08-01-2012, 10:33 PM
You are limited by your medium=water....Ice starts to form around 4c
Cheers
Stu

It means that for your example the lowest water temperature is 3,3 deg. C? Is it the limit? Could we go lower? What limits the lowest water temperature? Evaporation temperature? Evaporator construction?

install monkey
08-01-2012, 10:37 PM
not if u add salt! haha

Jacek
08-01-2012, 10:38 PM
york lchmChilled Water Leaving Temperature : R22 & R134a models : 4.0 C 10 C
R 407C models : 6.0 C 10 C
Chilled Glycol Leaving Temperature : R22 & R134a models : - 6 C 10 C
R 407C models : - 2 C 10 C
WATER /
Chilled Liquid Temperature Range through Cooler : 3.3 C 8 C
GLYCOL

Standard Condenser R22 models : 30 C 41 C
SYSTEMS
Liquid Leaving Temperaure : R134a models : 30 C 55 C
R407C models : 30 C 35 C



We are talking about centrifugal chillers...

stufus
08-01-2012, 10:38 PM
Then it's not "pure water" , could always p1ss in it.
Cheers
Stu

not if u add salt! haha

Jacek
08-01-2012, 10:39 PM
Hi
wouldnt try to go lower than 5 degc/.
good luck

Why? What is/are the limits?

goshen
08-01-2012, 10:39 PM
Hi
it is simple as water will freeze at 0 degc, but as said above crystals start to form at 2-3degc
this will lead to evap failure!
wouldnt go there !

Jacek
08-01-2012, 10:43 PM
Hi
it is simple as water will freeze at 0 degc, but as said above crystals start to form at 2-3degc
this will lead to evap failure!
wouldnt go there !

But if you are the evaporation temperature above +1 deg. C? We could maintain the evap temp above +1 deg. C...

stufus
08-01-2012, 10:50 PM
The type of chiller is irrelevant !!!
WATER IS WATER ! operating below 4c is dangerous territory with an expensive piece of kit
Cheers
Stu


We are talking about centrifugal chillers...

james10
08-01-2012, 11:12 PM
If you want to go below 5c you need to add a brine/glycol solution if you don't your unit will fail you
Can not get the water below 5 without an evaporation temp of 0c or below. Get yourself a piece of
Copper tube fill it with water seal both ends and put it in a freezer then you will see the results for
Yourself
As mentioned make/model machine is it

chillerman2006
08-01-2012, 11:25 PM
Hi Jacek

am with the other members who have replied here... 1*c is way too low

when commissioning i lock out the set point at 6*c and set ice/freeze protection to 4*c

also if evaporating at 1*c the only way the water will reach that temp is if you have no flow !

why do you require 1*c ? what are you cooling and what is the problem ?

chillerman

Jacek
08-01-2012, 11:36 PM
Hi Jacek

am with the other members who have replied here... 1*c is way too low

when commissioning i lock out the set point at 6*c and set ice/freeze protection to 4*c

also if evaporating at 1*c the only way the water will reach that temp is if you have no flow !

why do you require 1*c ? what are you cooling and what is the problem ?

chillerman

If we maintain the evap temp at +1 deg C, we could get the water temp at 2-3 deg. C (as goshen said). What is the problem? Is it a problem to maintain so low dt between evap temp and water outlet temp?

My question was the general one - how low we could go down with the "pure" water temperature using a ***** chiler...?

chillerman2006
09-01-2012, 12:01 AM
Jacek

you need to protect that evap/vessel

so normally you have ice/freeze protection set to 4*c and the low pressure switch set to 0*c

what would you set these to if you lowered the setpoint ?

mad fridgie
09-01-2012, 01:44 AM
You can have close to 0C easily if you use the right evaporator "jester chenson plate" or the like, you can use a closed heat exchanger, shell and tube or plate pack, but extreme care is required. very high water velocities and volumes, super control on suction pressures and a lot of other safeties.
In these case temp drop of water is minimal due to the high flow rates.

spinning wheel
10-01-2012, 03:58 AM
a york yk can go to 36 degrees F with smart freeze enabled

Jacek
10-01-2012, 08:31 PM
a york yk can go to 36 degrees F with smart freeze enabled

What's that?

Noori
10-01-2012, 09:44 PM
Hi jacek
the specific volume for water will increase at 4c so inlet water temperature should not reach to 4c.

stufus
10-01-2012, 10:07 PM
Smart freeze is a York control strategy on the their YK/YS chillers that allows the leaving water temp to be set as low as 2.2c .However programming the parameters to do this needs to be done by someone who knows what they are at.
The software constantly monitors the sensors and temperatures to avoid freeze up.
It's a big song and dance for the sake of 2.5c or a drop of anti freeze.
www.johnsoncontrols.co.uk/...chillers/yk/.../OI-EN-YK.pdf
Cheers
Stu

What's that?

monkey spanners
10-01-2012, 10:28 PM
Why do you want to use pure water as opposed to an anti freeze?

chillerman2006
11-01-2012, 09:16 PM
Carrier, York, Trane...


My question was the general one - how low we could go down with the "pure" water temperature using a ***** chiler...?

The general answer for a packaged chiller 'carrier, york, trane' is 6*c


You can have close to 0C easily if you use the right evaporator "jester chenson plate" or the like, you can use a closed heat exchanger, shell and tube or plate pack, but extreme care is required. very high water velocities and volumes, super control on suction pressures and a lot of other safeties.
In these case temp drop of water is minimal due to the high flow rates.

a bespoke system as above would require a 'mad fridgie' supply and fit plus regular tlc from a 'magoo'


a york yk can go to 36 degrees F with smart freeze enabled if you can supply the flow rates


Why do you want to use pure water as opposed to an anti freeze? maybe cost /$... heat transfer drops and cooling costs rise when anti-freeze is added

Jacek
02-05-2012, 06:21 PM
Hello,

Could someone tell me what the highest pressure ratio (evaporation temperature/condensing) for a R134a centrifugal chiller? Conditions are, for instance: evaporation temperature = 0-1'C, condensing temperature = "?" (what is the highest possible).

Tnaks in advance for input.

DITAW
28-05-2012, 01:52 PM
You are talking about the lift and that will be in the design of the chiller.

Jacek
29-05-2012, 12:22 PM
You are talking about the lift and that will be in the design of the chiller.

I am asking about that... What is the highest possible, let's say, lift?