Single circuit water cooling to +2*C

[hladotech]

Dear engineers!
I need a help!
Does anybody has expirience in water cooling with ***** chiller directly in evaporator to +2*C - ice water.
I don't know why each ***** chiller manufacturers (Daikin, McQuay, Trane, York, Ciat) do not garantee safe work in +2*C water cooling mode without glycol .
But ammonia chiller producers (Grasso, York, Maycom) use this metod every time with constant success and see no problems with this.
Please share yorue thoughts.

[mbc]

from +5 to low temp. is dangerous area for water cooled . why ? because your evaporator temp. goes to minus zero and ice up your evaporator ( Delta T) , So you have to add glycol. also my advice to you use E P R ( Evaporator Pressure Regulator)) to Protect your system for +5 to +8 degree and also put anti freezer thermostat.
in ***** Evaporator tube is a copper and in NH3 is steel. Copper is a weaker than steel against icing up.
In copper tube for seal they walls pipe (( banded)) in evaporator ((shell and tube))
In steel some company use welding in evaporator ((shell and tube))

[hladotech]

from +5 to low temp. is dangerous area for water cooled . why ? because your evaporator temp. goes to minus zero and ice up your evaporator ( Delta T) , So you have to add glycol. also my advice to you use E P R ( Evaporator Pressure Regulator)) to Protect your system for +5 to +8 degree and also put anti freezer thermostat.
in ***** Evaporator tube is a copper and in NH3 is steel. Copper is a weaker than steel against icing up.
In copper tube for seal they walls pipe (( banded)) in evaporator ((shell and tube))
In steel some company use welding in evaporator ((shell and tube))

When I have huge flow and thermal load i'll never ice up evaporator. I need to control boiling and outlet water temp. In DX S&T evap watr outsise tubes and to ice up it has to be no flow.
Ammonia pack chillers uses plates evap to reduce ammonia quant. And even in this case they do not affraid to produce +1*C icewater!!!
But i understand 1 problem - when I look at out water temp - it diffrent with water temp at tubes insaide evap.

[michaelm]

When I have huge flow and thermal load i'll never ice up evaporator. I need to control boiling and outlet water temp. In DX S&T evap watr outsise tubes and to ice up it has to be no flow.
Ammonia pack chillers uses plates evap to reduce ammonia quant. And even in this case they do not affraid to produce +1*C icewater!!!
But i understand 1 problem - when I look at out water temp - it diffrent with water temp at tubes insaide evap.

B”H

Hello hladotech
What is your application? Why cannot you use ice bank?

[sterl]

Look up ingredient water chillers and Chester Jensen, Omega, Turbo and etc.

If you want 2-deg C no more no less you will need some form of reciruculation on the water side....

[Magoo]

Definitly icebank type system at that temp without glycol.

[Superfridge]

You can achieve +2*C chiller water with flooded PHE evaporating at -1*C.

[mad fridgie]

You can get below 2C with fresh water,(but not normally single pass)
via a PHE, you need a high water velocity, to ensure that freeze up does not occur, I have in the past used glycol on the secondary side, with thermal buffer. I find trying to control the refrigeration load directly can be difficult (reaction time is to slow) Glycol supply has a minimum in the buffer of -3C then final control at the PHE via a 3 port valve and a decent PID controller.
The refrigeration circuit then becomes very simple and stable.

[INKYMART123]

try looking on google for buco falling film system. have used to chill water to 1 c. only prob we had was product blocking holes above evap and reducing water flow icing up evap. but thats production for u.