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Sweet ice
14-04-2009, 11:52 AM
Dear Everybody,

I am designing a refrigeration system for cold storage system, my refrigeration system will use the water defrost system.

On this system, i want to re-use the water after going through the evaporators to save the cost for operations. In this case, the water will guide to return to the water tank.
i'm worry that the water after doing defrosting will be cold so if the other evaporator run its defrosting or the troubles for the evaporator that is being defrosted, the cold water can not destroy the forst or ice on the fins.

Everybody can help me, what can i do in this case?
Thanks very much indeed!

Best regards,
Sweet ice.

Brian_UK
14-04-2009, 07:46 PM
Fit a heater.

Magoo
15-04-2009, 02:17 AM
Install a small cooling tower and bring water temp up to ambient, make water storage tank black plastic and position in the sun, Ho Chi Min City is hot and humid most of the year.
magoo

Sweet ice
15-04-2009, 02:52 AM
Thanks Brian,

We can use the heater to warm the warter,just for more question can you tell me the range of water temperature we must controll in the tank to insure safety? Nice day!

Br,
Sweet ice

Sweet ice
15-04-2009, 02:57 AM
Thanks Magoo,

Actually, i have already thought so much about this. in order to save the cost, we will use black plastic tank, but it also isn't suitable for the cool season.

I will re-see this carefully, but pls. help me more if you have more ideals.

Br,
Sweet ice.

josei
15-04-2009, 03:35 AM
Only two tips about :

1-be careful with the growth of microbial germs and dirt in water from thawing. avoid contact of outside air with this water.

2-plan a heat exchanger between thawing water and hot liquid refrigerant condensate.

chemi-cool
15-04-2009, 08:13 AM
After defrost, the water will be dirty from the evaporator. you will need a good filter.

Keeping the water warm can be done with a heating element [thermostat controlled], solar water heating, liquid line heat exchanging.

Do not heat the water too much, 25°C to 30°C at the most.

Sweet ice
16-04-2009, 12:39 PM
Hi Chemi-Cool,

Your informaiton is very usefull for me. We will controll the water temp. to do not over 25°C to 30°C. Otherwise, What is the lowest water temp. that we do not over them? Pls. help me?

chemi-cool
16-04-2009, 12:48 PM
If the water are too cold, it will take longer to defrost.

I would keep them at 25°C to 30°C .

How often do you intend to defrost?
What size water container are you planning to use?

Sweet ice
20-04-2009, 08:00 AM
Hi Chemi-Cool,

i would like to thanks very much for your information and nice day!

Brs,
Sweet ice.

Sweet ice
20-04-2009, 08:20 AM
Dear All,

I come back again, in this case i suggest we can controll the water in this range: limited minimum 20°C and maximum 30°C.

Has anybody have any ideals? Pls. advice??

Br,