Cold water machine the heat capacity of the frost and the compressor control system
Hot gas defrosting.
Use cold water machine compressor exhaust into the evaporator, superheated gases of heat and evaporation tube group and melting frost method.
the heat and water defrosting.
Mainly used for evaporation air cooler tube group.
Will first send A evaporation air cooler tube heat within the group, then A layer of frost melting and evaporation tube closely, and then through the hose to the outer surface water evaporation tube group, but will soon be completely melt frost layer.
Still can use heat after water & other;
Baking & throughout;
Water film evaporator surface, in order to avoid industrial cold water machine freezes again.
When it comes to several kinds of defrosting ways, in large and medium-sized device in the cold, hot gas defrosting is the most common one, no matter from energy saving, defrosting speed, remove the lubrication oil in the evaporator, is cannot be compared by other ways.
This method applies only to direct cooling system.
But system requires to indirect ling adopts steam heating heating defrosting defrosting or warm water.
Below is introduced for direct cooling system of hot gas defrosting and salt water defrosting system for indirect cooling system.
hot gas defrosting system way of gravity feed liquid ammonia defrost heat, work process is like this, when the evaporator is A need to defrost first ready for the drainage barrels of decompression.
Then close the drain valve, 2 3, at the same time open valve open width 1 let evaporator fluid for A recovery refrigeration, finally closed drainage barrels into the liquid valve.
visible evaporator defrosting operation process is relatively complex, in addition to the opening and closing a lot about fujian J f, to grasp the opportunity, otherwise there will be a accident or make the defrosting time extended.
If you plan to simplify the operation can also save drainage link t l closed when rich after 1, 3, 2, 4, open the valve using the high pressure gas pressure in the evaporator residual ammonia liquid into the drainage barrels.
But this approach because the initial stage of cold liquid and hot ammonia gas contact, must reduce the temperature of hot ammonia gas defrosting time longer.
the hot ammonia defrosting scheme, although hot hydrogen into the upper, the evaporator condensate liquid ammonia - since the lower outflow
But as a result of ling condensate before entering liquid regulating station need over a period of rising riser, so evaporator in lubricating oil can not be completely washed clean.
In order to improve the drainage method, this is not ideal for liquid can be adjust station is separated from drainage regulating station set up, the plan drainage stand alone setting adjustment and below the evaporator, the evaporator in lubricating oil can along with the row of forgiveness by weight