Absorption Refrigeration: How It Works

When most people think of the way that refrigerators work, they picture compressors and cold air. That’s why it’s so hard for many people to understand the concept of absorption refrigeration. It’s easy to see where their questions come from and why it can be a bit tricky to wrap your mind around. After all, how can the application of heat make something cold? It’s actually simpler than you might think.

absorption refridgerator

The Setup

One of the most interesting things about this kind of unit is that there are no moving parts. At all. With no electric motors or compressors that can fail, an absorption refrigerator is incredibly reliable. When these first hit the market, it meant that customers could enjoy marvelous warranties far beyond what was possible with traditional models.

An AR unit has four basic parts. The broiler, condenser, evaporator, and absorber come together within this ingenious design. Flexibility is another benefit that they offer. An absorption refrigerator can be powered by electricity as well as kerosene or gas. Adaptability is always a benefit, particularly when it comes to appliances.

Within these refrigerators, you’ll find ammonia, water, and hydrogen. The pressure within the tubes is great enough to condense ammonia at a certain temperature. Of course, different units are designed with different thresholds.

How Heat Makes Cold

Whether it’s fueled by electricity or gas, heat is applied to the boiler system. The temperature rises and boils the ammonia rather quickly. Small bubbles of the gas rise up, bringing with them an ammonia solution. This combination then enters the siphon pump and is split into two parts to continue the process.

Any of the weak solution is rerouted back into a tube and out of the way. The less dense gas travels into the vapor pipe. It then moves along to the water separator. In this chamber, the ammonia is purified from any water. The water is condensed and returned to the boiler system. The ammonia vapor, now unmixed, makes its way into the condenser.

Once there, the circulating air brings the ammonia back to a cooler liquid form and then transports it to the evaporator. This portion is full of hydrogen. It slides across the ammonia, reducing the pressure enough that it can once again evaporate. As it’s transformed back into a gas, it takes heat from the compartment and drops the temperature.

Ammonia and hydrogen are then moved to the absorber. The tube of weak solution, mentioned earlier, flows through this area and drags the ammonia away. The hydrogen rises back to the absorber coil, and the strong ammonia returns to its starting point at the boiler system.

Our Knowledge Is Your Friend

Even for less common setups like absorption refrigeration, you can count on Anderson Air Corps to always have the right information. Any time you require service, turn to us. We’ll cover all your needs—from emergency repairs to preventative maintenance—and we’ll do so with the best customer service around. Contact us today.