You are currently viewing Everything You Should Know About Marine Refrigeration Systems

Everything You Should Know About Marine Refrigeration Systems

Marine refrigeration systems play a crucial role in various industries, from shipping and logistics to offshore oil and gas operations. These systems are designed to meet the unique demands of marine environments, ensuring the safe storage and transportation of temperature-sensitive cargo.

For businesses operating in the marine sector, understanding the intricacies of these refrigeration systems is essential for maintaining product quality, complying with industry regulations, and optimizing operational efficiency.

Throughout this guide, we will explore marine refrigeration systems’ key components and operation principles and the factors influencing system selection, installation, and maintenance.

What Is a Marine Refrigeration System?

Marine refrigeration systems are essential for preserving food, beverages, and perishable items during transportation in the shipping and fishing industries.

They also play a crucial role in keeping safe materials like medicines, vaccines, and chemicals. These systems are designed to function effectively in extreme temperatures and challenging environments.

A marine refrigeration system’s primary purpose is to evaporate or compress a refrigerant gas to cool the refrigerated space inside a ship.

Similarly, boat refrigeration systems keep food, beverages, and perishables cool during transportation on boats. Whether it’s recreational, fishing, or large passenger ships, these systems can be used in various types of vessels.

Boat refrigeration systems operate by evaporating or compressing a refrigerant gas to lower the temperature within the boat’s refrigerated space.

boat refrigeration systems

They are designed to function efficiently in extreme temperatures and environments and typically consist of an evaporator and a compressor to remove heat and create colder temperatures.

How Does a Boat Refrigerator Work?

The process of how a boat refrigerator works involves the following steps: 

  1. First, the refrigerant gas is compressed to a high temperature and pressure in the refrigerator compressor.
  2. Then, it passes through coils or pipes, dissipating the heat into the surrounding air.
  3. Once cooled, the refrigerant enters an evaporator coil, which is expanded back to low pressure and temperature.
  4. The cold refrigerant then absorbs the heat from the food or perishables in a small insulated space.
  5. Finally, the warmed refrigerant is pumped back to the compressor to repeat the cycle, keeping the boat refrigerator cool and preserving perishable items.

Regular maintenance is essential to keep these systems working efficiently and safely. This maintenance includes checking for leaks, replacing filters, and cleaning coils as necessary.

What Are the Different Types of Marine Refrigerators?

Various types of marine refrigeration systems are available, each with unique features and benefits. Here, we will explore the different types of marine refrigerators to assist you in choosing the right system for your vessel.

Self-Contained Units

For smaller boats, self-contained units are popular because of their easy installation and minimal space requirements. These units, powered by 12V or 24V DC, use thermoelectric cooling technology to maintain temperatures between 0°C and 10°C for refrigerated food storage.

self-container units

Thermoelectric Units

Thermoelectric units operate on 12V DC power and utilize the Peltier effect instead of refrigerants. While they are low-maintenance, noiseless, and easy to install, they are less efficient than other types. They can cool boxes by 40-50 degrees lower than the ambient temperature but are impractical in tropical or hot climates due to insufficient cooling power.

Holding Plate Systems

Holding plate systems, commonly used in larger vessels, employ a large evaporator plate to store cold air. Fans circulate this air throughout the boat, maintaining consistent temperatures. Although this method requires more space, it is suitable for extended trips and warmer climates.

Compressor Units

Compressor units are the most efficient type of marine refrigeration. They use chemical-based cooling systems powered by 230V/50Hz AC power.

Available in various sizes, they are ideal for larger vessels and longer journeys, serving refrigerator and freezer applications. However, they require more installation effort and are comparatively expensive.

To determine the best marine refrigeration system for your boat or yacht, consider vessel size, intended use, and operating climate. Self-contained units suit small boats with minimal cooling needs, while compressor units are suitable for larger vessels in hotter climates.

Regular maintenance and inspection are crucial to ensure efficient and safe operation regardless of your type. Following the manufacturer’s instructions during installation, operation, and maintenance is essential for longevity and to avoid potential risks associated with improper installation.

By selecting and maintaining the appropriate marine refrigerator properly, you can maximize its performance and lifespan while ensuring a safe and efficient cooling system onboard your vessel.

What Size of Refrigeration System Does My Boat Need?

When purchasing a commercial-size refrigerator for your boat, it is crucial to consider the appropriate size to maximize your investment.

Determine the Type of Boat You Have

To begin, it is essential to determine the type of boat you have, whether it is sail or motor-driven, and its overall size. Different types of boats require different sizes of refrigeration systems.

Calculate Your Storage Needs

Calculating your storage needs is the next step. Consider the type of food and drinks you plan to store in the refrigerator. This will help you determine the required storage space and subsequently narrow down the size of the system.

Energy Consumption

Energy consumption is an important factor to consider. By assessing how many amps a commercial refrigerator uses, you can determine the most suitable system for your needs and ensure long-term cost-effectiveness.

Measure the Available Space

Measuring available space is crucial to ensure the chosen system properly fits your boat’s cabin or galley. Taking accurate measurements will prevent purchasing a system that is too large or small for the designated area.

cruise space optimization

Select a Reliable Brand

Selecting a reliable brand is also emphasized. Choosing a refrigeration system from a reputable brand ensures durability and longevity.

By following these tips, you can confidently select the best-size refrigeration system for your boat. A properly sized system guarantees that your food and drinks remain cool and fresh during maritime adventures.

Which Refrigerant Is Commonly Used in Marine Refrigeration Systems?

Refrigerants play a crucial role in maintaining the efficiency and reliability of marine refrigeration systems. However, choosing the right refrigerant can take time due to the many options available.

To help make this process simpler and quicker, we have gathered the most commonly used refrigerants in marine applications.

Types of Refrigerants Used in Marine Refrigeration Systems

Chlorofluorocarbons (CFCs) were widely used in the past but are now being phased out due to their negative environmental impact. Nonetheless, CFCs such as R11, R12, and R115 are still commonly used in marine vessels for their excellent cooling capacity and performance.

Hydrochlorofluorocarbons (HCFCs) are another type of refrigerant used in marine refrigeration systems. They have a shorter atmospheric lifetime and lower ozone-depleting potential than CFCs. R22, R123, and R-124 are commonly used HCFC refrigerants in the marine industry.


R12 stands out as the most popular and widely used marine refrigerant among the refrigerants discussed. Developed in 1928, R12 was the first refrigerant used for automobile air conditioning due to its non-flammability and stability. Although R12 is becoming obsolete, many marine vessels still rely on it for its long-standing performance and reliability.


R134a, a hydrofluorocarbon (HFC) refrigerant, is popular in marine refrigeration systems. It offers non-toxicity, non-flammability, and a low ozone depletion potential. However, it has a high global warming potential (GWP), which still threatens the environment.

refrigerant for marine systems


R407C is another blend of HFC refrigerants commonly used in marine refrigeration systems. It has low toxicity, flammability, and ozone depletion potential. As an effective alternative to the older R-22 refrigerant, R407C offers a more environmentally friendly option.

The production of R22 has been banned in many countries, leading boat owners to seek eco-friendly alternatives. Two popular options are R134a and R407C, each with advantages and disadvantages compared to R22.

When choosing a refrigerant for marine refrigeration systems, it is important to consider environmental impact, performance, and reliability factors. HFCs are replacing CFCs and HCFCs with lower ozone depletion potential, although they still have some effect on the environment. Boat owners should carefully evaluate the advantages and disadvantages of different refrigerants to make an informed decision.

What Does the Compressor Do in the Refrigeration System?

The compressor is a vital refrigeration system component, particularly in marine applications such as cruisers, yachts, and boats. Understanding how compressors work in a refrigerator is essential for identifying any issues with the marine refrigeration system and taking prompt action.

Its primary function is to compress the refrigerant, crucial in keeping food and beverages cool and fresh, even when far out at sea. Without the compressor, the refrigeration system could not maintain the desired temperature.

compressor for marine temperature

The marine refrigeration system consists of several components that work together. In addition to the compressor, these include the condenser, receiver, drier, solenoids, expansion valve, evaporator unit, and refrigerant.

The condenser converts the high-pressure gas the compressor produces into a liquid form by releasing heat energy into the surrounding air. The receiver acts as a storage tank for the liquid refrigerant, while the drier removes moisture and contaminants from the refrigerant before it enters the evaporator.

The solenoids are electrically operated valves that regulate the refrigerant flow, allowing for switching between cooling and heating modes. The expansion valve reduces the pressure of the liquid refrigerant, facilitating its evaporation into a gas.

The evaporator is responsible for absorbing heat energy from the air and transferring it to the refrigerant, leading to cooling. The refrigerant runs through all the components of the refrigeration system, changing between gas and liquid states as it absorbs and releases heat energy.

Compressors work by increasing the pressure of the refrigerant, allowing it to absorb heat energy more efficiently. They are the main component of the refrigeration system and play a crucial role in circulating the refrigerant and maintaining the desired temperature. The type of compressor used depends on the specific requirements of the marine refrigeration system, with reciprocating single or two-stage compressors being commonly used.

Regular maintenance ensures the compressor’s continued efficiency and effectiveness, ensuring your food and beverages stay chilled during marine adventures.

What Is a Cold Plate System?

A cold plate is a stainless steel container placed inside a refrigerator or freezer box. It contains coiled tubes through which a refrigerant flows.

When the fridge runs, the refrigerant freezes, turning into a solid state. Once frozen, the compressor shuts off, and the cold plate acts as a large ice block, slowly melting back into a liquid while extracting heat from the fridge.

The size of the cold plate and the temperature inside the box determine its cooling duration, which can last up to 24 hours. It operates as a temperature battery, storing cold when there is excess power and cooling when capacity is limited. Typically, a high amp draw 120V compressor is used to freeze the cold plate quickly.

Most cold plates are made of metal with channels that allow the refrigerant to flow. These channels come in different shapes and sizes, enabling the cold plates to absorb and transfer heat efficiently. The heat transfer rate depends on factors such as the liquid used, the flow rate, and the material of the cold plate.

Cold plate systems offer several advantages in marine refrigeration, particularly when space is limited. Unlike traditional evaporators, cold plates can be placed directly into the walls or floor of the refrigeration compartment, maximizing storage capacity.

Additionally, cold plate systems can operate without a constant power supply. Charging the plates during periods of high power availability, the refrigeration system can continue to cool even when the boat’s generator is turned off. This reduces noise and fuel consumption and provides an emergency backup cooling solution.

If you need a new marine refrigeration system, consider the benefits of a cold plate design for your vessel. These systems are efficient, reliable, and compact, making them ideal for boat owners looking to enhance comfort and storage on board.

Obtain the Finest Cooling Systems for Your Vessel

At Cruise RO Water and Power, we understand the importance of having a high-quality refrigeration system for your boat. That’s why we offer a range of options, including cold plate cooling systems and standard systems, to cater to your specific needs. Our reverse osmosis water makers and refrigeration solutions are designed to meet the demands of marine environments, ensuring optimal performance and longevity.

By choosing Cruise RO Water and Power, you can trust that you’re getting the best cooling system for your boat. Our expertise in marine refrigeration and our commitment to customer satisfaction make us the preferred choice for many boat owners. Whether you want to increase comfort or maximize storage space, we have the perfect solution.

Don’t settle for subpar refrigeration systems that compromise the well-being of your perishable goods and overall onboard experience. Contact us today to explore our range of marine refrigeration systems and find the one that suits your needs. Trust Cruise RO Water and Power to provide you with the best cooling system to enjoy your boating adventures to the fullest.

Leave a Reply