What is the difference between ammonia refrigeration system and fluorine refrigeration system?

In the early years, many ice factories and cold storage manufacturers preferred ammonia as their refrigeration system, but they found the following inconveniences during years of use

1. The cooling efficiency is getting lower and lower;

2. The equipment occupies a large area, and there is no land available for expansion;

3. The cost of training a qualified ammonia machine operator is high;

4. The longer the service time, the older the equipment, there are potential safety hazards, and the inspection cycle of various pressure vessels and valves is short, which will affect production and bring operating cost burden

What is the difference between ammonia refrigeration system and fluorine refrigeration system?
Why are more and more people in the industry starting to change ammonia to fluorine?
CBFI will answer you from the following aspects.

01. Why does the longer the ammonia system is used, the lower the cooling efficiency?

Ammonia (R717) is a toxic and explosive refrigerant, so it is not allowed to be used as a direct refrigerant, and it is generally used in the secondary heat exchange refrigerant system. There is oil in the compressor, and the density of ammonia is lower than that of oil. In the accumulator and evaporator, the oil will deposit to the bottom. The solubility of ammonia in lubricating oil is very small. There are more and more oil film and grease on the surface of the heater, the heat transfer performance is getting worse and worse, and the cooling efficiency is getting lower and lower, which greatly affects the heat transfer effect.



Fluorine (R22) can dissolve oil to varying degrees, is not easy to form oil film in the system, and has little effect on heat transfer. Fluorine (R22) can adapt to different refrigeration temperature requirements, and the lowest evaporation temperature that can be produced is -120°C.

02. Why does the ammonia system occupy a larger area?

Two-stage compression is adopted (the evaporation temperature is lower than -28°C), the pump fluid system and the oil return mechanism are more complicated and the system is huge;
A separate computer room is required. Ammonia is poisonous, so the layout of the computer room cannot be built in the common building of the factory building; the ammonia machine is noisy and vibrating when it is running, and the dynamic load generated is large, and the impact on the storage body cannot be ignored;


Fluorine (R22)

Small size, less land occupation, no need to set up a single machine room, greatly saving space

low unit noise

03. Why is the labor cost of the ammonia system more expensive?



The control of storage temperature in the domestic ammonia system is generally fully manual control, and specific personnel are required to determine the number of compressors to start or stop. Since all manual operations are required, it depends on the technical level and sense of responsibility of the operator;
According to the survey of industry operators, it takes 5-10 years to train a qualified ammonia machine operator; and the aging of special equipment operators is serious, it is difficult to find suitable young special operators, and the labor cost is high;
Even for qualified operators, there are many uncertainties in the operation of machines and systems, such as the operator's sense of responsibility and excessive fatigue will affect the normal use of equipment;
The ammonia system requires 24-hour manned duty and adjustment;


Fluorine (R22)

The direct expansion system fully realizes automatic control, greatly reducing the cost of manual operation

The protection equipment is complete, and the unit is equipped with complete protection measures such as voltage protection, temperature protection, current protection, and pressure protection

Can realize computer control, wide range of energy regulation



04. Why is the ammonia system more complicated to install?


Ammonia is a flooded system;

The system is huge, with many auxiliary machines and complicated pipelines;

The construction and installation procedures are complex and the construction period is long;

If there is no professional on-site installation, it is easy to increase the hidden danger of failure. For example: the evaporating pipe, the ammonia pipe, the valve rupture, disengagement, etc. cause ammonia leakage accidents, the ammonia valve spool falls off, and gets stuck in the valve body;



Fluorine (R22)

Fluorine can be used as a direct expansion system

The development of parallel technology has been very perfect, and the normal operation of the entire system will not be affected by the failure or maintenance of individual compressors during operation

The average running time of each compressor in the parallel unit is much shorter than that of the single-unit cooling system, and the service life of the compressor is longer