R404a condensing unit refers to a unit that uses R404a refrigerant gas.
This type of condensing unit generally uses a small refrigeration unit, Maneurop condensing unit, freezer condensing unit, Secop condensing unit, Tecumseh condensing unit, Bitzer condensing unit, etc.
Precautions for R404a Condensing Unit Instead of R22 Refrigerant Condensing Unit
The safety measure that needs to take before replacing the R22 refrigerant condensing unit with R404A condensing unit.
R22 refrigerant gas has a considerable amount of fault or failure to meet a certain standard to save the ozone layer from harm.
So another environmentally friendly refrigerant can take the place of R22 though It is still the largely used refrigerant in the global refrigeration industry.
So the issue arises when it comes to converting existing R22 refrigerant gas into R404A refrigerant unit.
You must consider their differences before replacement in practical uses.
There are some best practices that are very important to follow in the piston compressor refrigeration system while you use R404A refrigerant.
We will make a clear sense to guide you in this brief analysis to guide you about how to use HFC green refrigerant better.
◑ R22 refrigerant condensing unit uses mineral oil while R404a refrigerant condensing unit use HFC and polyol Ester oil as their lubricating oil.
So there is a big difficulty while using R404a instead of R22 as you must use lubricating oil, and PVE ester oil to replace mineral oil or R22.
◑ The exhaust flow rate and resistance will get bigger when you replace R22 with R404a because the exhaust pressure of R04a is 1.2 times and the flow rate is 1.5 times of the R22 condensing unit. So you should expand the heat disposal volume rate of R404A refrigerant by 20% to 30% compared with R22.
◑ There are many different separations exist between R22 refrigerant and R404a refrigerant condensing unit such as the saturation pressure of both of this refrigerant is not equivalent in the same temperature.
So there are some differences between the thermal expansion valve of R22 and R404a. In this case, our suggestion is to use a special expansion valve as a substitute for others.
So you can solve the problem of monitoring different saturation pressure efficiently.
◑ Compearing the vapor pressure within R404a and R22 condensing unit, it’s not the same and R22 has less pressure.
So there is the same risk while operating the R404a condensing unit. To solve this issue, you need to change the maximum allowable working pressure of the pressure vessel.
It is a very important step to avoid spurious function while small process upsets.
◑ Another important step is to transform the compressor parts if the compressor is not the same such as AC contactor diameter, cable, or thermal relay.
As the R404a compressor is bigger and R22 is comparatively smaller, so you should adjust it.
◑ You also need to notice to ensure a larger test pressure of the gas tightness test and system vacuum than the R22 refrigerant condensing unit.
That is because the vapor pressure of these two refrigerants is not the same. Having a low water content for R404a refrigerant condensing unit than R22 is also need to consider.
◑ When the temperature and pressure fluctuate, the intentness of the R404a condensing unit also switches to becoming different.
It is a big issue affecting the manufacturing, commissioning, troubleshooting, or repairing of the units.
The unit’s heat transfer operation can also be affected by it, mainly if there is a leak on refrigerants, you should unpack all the contents from the container or replace it to acquire the design refrigeration effect and proportion of the blended elements, or else it can be more terrible.
The R404A refrigerant required more neatness than the R22 refrigerant.
So it’s is a very essential factor to keep the R404a cleaner to monitor water and other liquid diffused in a vapor.