Yearly Archives - 2023

Gold fin and Blue fin difference

Gold fin and Blue fin

Gold fin and blue fin are types of coatings applied to the fins of heat exchanger coils, commonly used in air conditioning and HVAC systems. 1- Gold Fin: Gold fin, also known as golden hydrophilic fin, typically refers to a type of corrosion-resistant coating applied to the aluminum fins of heat exchanger coils. The "gold" color comes from the protective coating, which is often a hydrophilic layer. This coating helps prevent corrosion, enhances heat transfer efficiency, and discourages the...

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The role of coils in the refrigeration cycle

The role of coils in the refrigeration cycle

Coils are known as the most important component in air conditioning and refrigeration systems. One of the most important heating and cooling cycles is the refrigeration cycle. Condenser coils, usually located in the outdoor unit of the system, help to dissipate the heat that has been absorbed from the indoor space. These coils operate at high pressure and temperatures and help to convert the refrigerant from gas to liquid. On the other hand, the evaporator coils, which are located inside...

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Flooding

Flooding (also known as ‘flood back’) is the term used to describe the condition when liquid refrigerant reaches the compressor. This occurs when the amount of liquid fed to the evaporator is more than can be evaporated. There are a number of possible causes of flooding including: • TXV oversized for the application • TXV misadjusted (superheat too low) • System overcharged with refrigerant • Insufficient airflow through evaporator • Dirty evaporator • Evaporator fans not operating • TXV bulb not...

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Evaporator Vs. System Superheat

Q: What is the difference between evaporator superheat and system superheat? Superheat varies within the system depending on where it is being measured. The superheat that the thermal expansion valve is controlling is the evaporator superheat. This is measured at the outlet of the evaporator. The refrigerant gains superheat as it travels through the evaporator, basically starting at 0 as it enters the evaporator and reaching a maximum at the outlet as the refrigerant travels though the evaporator absorbing heat. System superheat...

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What is Evacuation

Q: What is the purpose for ‘evacuating’ a refrigeration system? Evacuating a refrigeration system serves two primary objectives: 1. Removes non-condensables 2. Dehydrates (removes water vapor) If non-condensables such as air are not removed, the system will operate at higher than normal condensing pressures. This happens because the air is trapped at the top of the condenser, effectively reducing the condenser capacity. Increasing the condensing pressure results in higher compression ratios and higher discharge temperatures, both of which decrease system...

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Compressor Floodback

Floodback occurs when liquid refrigerant returns to the compressor during the running cycle. Often a service contractor may see a compressor that failed due to floodback, but because of the severity of the damage, he may misdiagnose the problem. System-based causes of slugging and floodback may be different from each other; finding the root of the problem is essential to prevent it from happening again. There can be multiple system causes of floodback, even as basic as lack of airflow because...

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