Everything You Need To Know About Ammonia Refrigeration

You’re probably familiar with the term “ammonia”, but how does it come into play with refrigeration systems? 

Ammonia is a naturally occurring colorless gas that is a compound of nitrogen and hydrogen. When used in refrigeration systems, ammonia works to capture and transfer heat energy to keep it separate from the cooling process. 

Ammonia Uses 

Besides refrigeration, Ammonia has a variety of uses in most major industries. 

Ammonia as a Fertilizer 

Ammonia contains the highest levels of Nitrogen in commercial fertilizers. Nitrogen is used to provide nutrition for plants, but nitrogen in its natural state is unstable. It wasn’t until 1910 when two chemists created the Haber-Bosch process where nitrogen is captured from the air and put under high pressure and temperatures to create ammonia NH3. Almost 90% of all ammonia products are for ammonium nitrate fertilizer for plants and food. 

Household Ammonia 

Common household cleaning products contain ammonia that is diluted with water, which is also known as ammonium hydroxide. Ammonia has proven to be a great chemical to cut through grease and scum, plus it also helps clean glass without streaking. 

Industrial Ammonia Uses 

Since ammonia is very effective at absorbing heat, it’s often used in industries with air-conditioning equipment. Ammonia also acts as a building block chemical for some industries and a stabilizer for other industries. 

Ammonia is used in all of the following industries: 

• ● HVAC and HVACR 
• ● Fabric manufacturing 
• ● Pesticides 
• ● Food and Beverage industry 
• ● Water treatment and purification 
• ● Plastic manufacturing
• ● Explosive production 
• ● Pharmaceutical manufacturing 
• ● And many more! 

Ammonia Dangers/Risks 

Ammonia without hydrogen is a gas known as anhydrous ammonia. In this form, anhydrous ammonia is lighter than air and has a very pungent odor. Gaseous ammonia is also flammable and combustible. The Clean Air Act requires that companies storing over 10,000 pounds of anhydrous ammonia must submit a risk management plan. When handling anhydrous ammonia, be sure to wear protective gear like gloves, goggles and a face respirator or shield. 

Household ammonia products like Windex only contain about 10% of liquid ammonia that is much less dangerous than anhydrous ammonia. Like most cleaning products, it’s recommended to keep ammonia products away from children and pets. 

In any state, ammonia is extremely soluble in water and moisture. 

Traces of ammonia can enter the human lungs, eyes, throat, and skin. This can cause irritation, burning, and sometimes lead to serious complications depending on the concentration of ammonia. Always use caution when using ammonia products and be sure to never mix ammonia with bleach - this causes chlorine gas that can cause acid burns. 

Industrial Refrigeration Ammonia Systems 

Now that you have a better understanding of ammonia itself, it’s time to learn more about how industrial refrigeration ammonia systems work. 

Although industrial refrigeration systems are much larger than household fridges, the basic function of refrigeration revolves around the liquid refrigerant ammonia. During the entire cycle of vapor compression, the refrigerant is constantly working to trap and release heat until the compressor reaches its preset temperature. 

Here are the 8 steps to industrial ammonia refrigeration: 

1.  Right before the evaporator, the liquid refrigerant enters the expansion valve from the receiver. 
2. The expansion valve allows the high pressure and temperature liquid to cool down and drop pressure, which causes the liquid to become a mixture of vapor and liquid. This is required for the correct amount of heat transfer as the ammonia flows through the evaporator. 
3. The liquid refrigerant and vapor mixture absorbs heat from the evaporator coil. The compressor will automatically cycle to maintain a preset temperature or pressure.
4. The suction line begins to draw the refrigerant towards the compressor. Once the refrigerant reaches the compressor, the heat and vapor begin to compress under high pressure. 
5. The refrigerant then enters the discharge line as a high temperature/high pressure vapor on its way to the condenser. 
6. After the discharge line, the refrigerant vapor goes through the condenser coil. At this point, the vapor condenses into a liquid from the stored latent heat in the refrigerant. Typically there is water and air being forced over the condenser coil in order to remove the heat and condense the ammonia vapor. 
7. The saturated liquid refrigerant now goes through the receiver where some of it is evaporated. Enters the receiver where it is stored and readily available for use when the system components require liquid. 
8. The refrigerant has almost made its way through the system's cycle. After going through the receiver, the saturated liquid refrigerant enters the liquid line and then reaches the expansion valve to begin the process over again.

Ammonia Refrigeration System Maintenance 

As you can see, industrial refrigeration systems rely on a functioning cycle of systems. If one system isn’t performing, the whole system can get disrupted. Proper cleaning and maintenance of refrigeration systems is important and it can help prevent costly repairs from happening. Even small amounts of dust or dirt can make it difficult for refrigeration parts to maintain the right temperature. Besides normal interior and exterior cleaning, you should also commit to several deep cleans about every 3 months. 

During a deep clean, check the following: 
● The condenser coil 
● The evaporator coil
● Door gasket seals 
● Air filters and ventilation 
● Drain pans and tubes 
● Any areas with condensation 

All of these parts should be wiped down and inspected for wear, splits, or any other component failures. If any parts need to be replaced, you should check your manufacturer recommendation for the appropriate serial and model number. You can also call us here at FrostPoint for all your industrial refrigeration questions.

FrostPoint Industrial Refrigeration Parts 

Whether you need replacement parts or a whole new system, we supply system parts from all major industrial refrigeration brands at great prices. We understand that finding the right part for your system can be difficult and that’s why our customer care team is ready to answer any questions you have. Each of our representatives are backed by over 20 years working in the industrial refrigeration industry. To find any refrigeration part, simply type a keyword in the search bar on our website or give us a call at 262-261-6100.