Cooling with Freon: The Facts.
In our Ammonia Refrigeration Simplifed paper we told you everything you wanted to know about ammonia refrigeration but were afraid to ask. But ammonia isn’t the only refrigerant used in food processing, meat, dairy, bakery, and cold storage facilities. Freon (a trademark of Dow and the most recognized halocarbon chemical) is preferred by many processors. So what are the pros and cons of Freon? Read on to learn the facts from Food Plant Engineering team of experts.
Halocarbon Refrigeration Basics
Halocarbons come in two flavors: one is methane-based and the other ethane-based. Because of ozone-depletion concerns, methanes are being eliminated from industrial use. (As part of the Montreal Protocol, the widely-used halomethane R-12 was phased out in 1995. Similarly, R-22 is scheduled to cease production in 2020.) Ethane-based halocarbon systems are very common today in certain types of processing facilities. If you’re considering such a system, discuss the following:
01Refrigeration System Cost: In order to make your decision (between ammonia and Freon), you run a load calculation for a rule of thumb for costing purposes. If a refrigeration system load is less than 100 tons (1.2 million Btu/h), you most likely will need a halocarbon system. Of course, halocarbon (Freon) can be used in much larger systems as well, and many choose to do so for various reasons. In addition, installation of a Freon system is usually less expensive than ammonia for certain applications, a fact that can greatly affect a project’s budget.
02Product, Capacity, and Temperature Requirements: When choosing between ammonia and Freon, consult an engineer well-versed in the capabilities and limits of each system. Such an expert will consider the volume of product, the type of product your facility produces and the temperature needed to cool the product. For example, Freon is good for cooling up to 60,000 lbs. of meat per hour from 150-degrees Fahrenheit to -10 degrees Fahrenheit. Bread and cheese products have similar boundaries.
03Efficiency: Typically, an ammonia refrigeration system will be more efficient than a Freon system. However, a properly designed Freon system can rival an ammonia system and can even be up to 25-percent more efficient than a poorly-designed ammonia system. This is why it is important to have an experienced engineer design a system to fit your needs.
04Regulations: Freon is odorless, yet toxic, so you have to have oxygen sensors in your room. That’s part of the requirement of the regulations for operating a halocarbon refrigeration system. Be aware that regulations vary by state and also by localities within the state. And regardless of the refrigerant used, some states require a dedicated refrigeration engineer to be on site if the system meets certain size criteria.
05Flexibility: Two types of Freon systems exist. Unitary equipment is essentially like the air conditioner in your home. You have a condensing unit outside your house and a fan coil in the room. You have one or two fan coils per condensing unit. If the condensing unit goes down, you’re out of refrigeration. With a rack system (typically used in the grocery industry), a steel rack with a steel frame will contain multiple compressors. If one compressor fails, the others will help carry the load. A remote air-cooled condenser is located outside the building, typically on the roof. This function of this condenser is to propel the heat to the outside environment.
06Maintenance: Unlike ammonia systems, a Freon system can be easily maintained by a well-trained heating and air conditioning contractor.
07Comfort Level: Maintenance personnel are usually familiar with Freon and have a comfort level working on halocarbon systems. This can mean the difference between using a local service contractor instead of one from a different city or even state. Obviously, this depends on your plant’s location. Finding a reputable service contractor is something to consider in the design stages of your facility.
Essentially, refrigeration is simply pumping heat from one area to another. You pump it from the inside to the outside. How you accomplish this task, however—what system you use in your facility—can greatly affect the bottom line of your business and the safety of your employees and your product. We urge each potential client to choose a design firm carefully. This isn’t the place to cut corners. And of course, we’d like for you to contact Food Plant Engineering when making these decisions. Every system is unique and should be customized to your needs. “If you want to refrigerate a case of beer, buy a cheap refrigerator,” advises one of our engineers. “If you’ve got a plant, get an engineer to design the system that is going to be the most efficient for you.”
Hopefully we've answered a few of those questions about Freon refrigeration that you were afraid to ask!