Laboratory Refrigerators and Freezers are made by a thermally insulated compartment and a mechanical, electronic, or chemical heat pump that transfers heat from the interior to the exterior to keep the internal temperature below room temperature. Laboratory Refrigerators and Freezers must be 100 percent hygienic and 100 percent dependable. Laboratory Refrigerators and Freezers can preserve various samples and specimens which can cool in laboratories for further use. It helps to reduce the risk of bacterial contamination and volatile material explosions.
Laboratory Refrigerators and Freezers needs proper air circulation and a fan to maintain a consistent temperature to operate with high levels of accuracy. The state of the substances changes from liquid to solid below the freezing point which phenomenon is called freezing.
Freezer helps to keep biological samples and flammable chemicals at temperatures between -800C and 100C. Lab freezer is used very much in different fields such as laboratories, blood banks, hospitals, production facilities, material testing labs, and diagnostic centers. The samples stored in refrigerators are between – 50C and – 150C, whereas the usual range for storing tested samples in freezers is between -200C and -150C.
Working Principle of Laboratory Refrigerators and Freezers
Firstly, the refrigerant gas is compressed and raises its temperature and pressure. In the meantime, heat exchange coils help to the production of heat by the pressure. Then the refrigerant liquefies into liquid form after starting cool and it passes through the safety valve. The liquid refrigerant expands and evaporates when it moves from the high-pressure region to the low-pressure region. It has the ability to absorb heat during the evaporation process and has a cooling effect. Coils in the refrigerator help absorb heat and maintain a chilly interior.
Heat is transferred from a substance’s body to the environment after transforming the substance from a liquid to a solid form. The kinetic energy of liquid molecules decreases owing to heat production, and they move more slowly. The molecules come together and turn into solids during freezing due to the reduction of the particles’ mobility.
Instrumentations of Laboratory Refrigerators and Freezers
There have many components of Laboratory Refrigerators and Freezers which are discussed below:
Refrigerant: It is very essential for a refrigerator. It has the ability to move through the various components of the refrigerator and change from a gas to a liquid and back to a gas.
Compressor: This part is the heart of the refrigerator where the cooling process begins. The refrigerant gas can be sent to the condenser at a higher temperature and pressure to the compressor, which is powered by a motor.
Condenser: It places on the back side of a refrigerator and it is probably pretty dusty. It helps to cool the refrigerant and condenses the transferred hot vapors, changing from a gas to a liquid.
Capillary Tube: This part comprises a tiny set of copper tubes that help to reduce the temperature and pressure of the liquid refrigerant.
Evaporator: This part helps to keep the contents chilled. It turns the remaining refrigerant liquid to vapor again, which the compressor uses to restart the process creating the ideal atmosphere for preserving food.
Accessories of lab refrigerator
Thermistor: The internal temperature of this device can be monitored by this part.
Evaporator Fan Motor: This part helps to distribute cold air across the freezer and refrigerator compartments
Condenser Fan Motor: This part helps to drive air through condenser coils in refrigerators with compressor compartment mountings to cool the refrigerator and dissipate heat.
Water Inlet Valve: It helps to produce enough water pressure to open the valve and dispense water into the ice tray to make ice.
Water Filter: It helps to prevent water from reaching the ice maker, preventing ice formation.
There are also thermometers and alarms for various purposes.
Thermometers and alarms are fitted.
Refrigerator Types
Explosion-proof refrigerators: This type of refrigerator is used to store flammable liquids and dangerous chemicals. This kind of refrigerator is safe to use with flammable materials because there are no electrical appliances in the storage space.
Lab fridges: These kinds of refrigerators are made to keep temperatures stable and to display temperature information digitally. It should have a lock and clean facilities for the preservation and cooling of samples properly.
Blood bank refrigerators: This kind of refrigerator has the ability to maintain a constant temperature to store and safeguard chilled whole blood, blood components, and blood products.
Chromatography refrigerators: These kinds of refrigerators are designed for scientific experimentation.
They work best in laboratories where precise temperature controls and stability are needed for medical samples and procedures. For instance, a chromatography setup might be made inside the refrigerator chamber of a lab refrigerator.
Lab Freezer Types
Ultra-low temperature Freezer: This kind of freezer is perfect for storing items that require very low temperatures in laboratories and healthcare facilities.
Chest Freezer: Chest freezers are suitable for labs that need to keep huge goods in a single unit because they are efficient.
Under-Counter Freezer: Under-counter freezers have various configurations, including all-purpose, explosion-proof, and the option for explosive material storage. These have forced air ventilation, so extra clearing space is unnecessary for the general-purpose type.
Upright Freezer: Upright Freezers are equipped with shelving units and allow for the efficient organization of samples and making the most of the available space.
Laboratory Refrigerators and Freezers Operating procedures
Laboratory Refrigerators and Freezers should be labeled all the materials for storing in the refrigerator. It must be securely positioned and thoroughly sealed for all containers in a refrigerator or freezer. It should not be kept food or beverages intended for human consumption in a freezer or refrigerator used in a lab. It must be verified The compatibility of the substances kept in the refrigerator.
It should not keep the flammables in a household refrigerator with a flash point lower than 37.8°C. It must be avoided to use Aluminum foil, corks, and uncoated glass stoppers for closed containers. Plastic trays can be used in refrigerators and freezer compartments for storing various items. It can store a limited amount of chemicals that will be needed for a reasonable time in storage. It should be cleaned out yearly to prevent any contamination.
Applications of Laboratory Refrigerators and Freezers
Laboratory Refrigerators and Freezers can store various samples and specimens at a definite temperature to ensure that they do not become spoiled, while freezers accurately freeze items rather than cool them. It helps to maintain the reagent stability that is needed in the chemistry analysis by facilitating a precise temperature control system during refrigeration. It helps to maintain the good quality of the microbiological media.
