How to Differentiate the Condenser Coil from Evaporator Coil

Nothing is more confusing than the condenser coil and evaporator coil. They look similar, they’re both in your AC unit, and they both do different things. But how can you tell one from the other?

Well, it’s not as hard as you think! There are a couple of ways to differentiate them—and there’s no need to worry—we’ve got you covered! 

In this article, we will compare condenser and evaporator coils and help you understand these two parts of your air conditioner system and when it’s time to call a qualified HVAC technician.

What Is An Evaporator Coil?

An evaporator coil is the unit of your AC that absorbs heat and cools your home. It’s often found in home furnaces and air conditioners, where the heat produced by combustion or electrical resistance is transferred from the furnace or AC unit to the air in your home.

The coil is made of metal and designed to be submerged in water. In most cases, this means that part of your furnace or AC unit will have to be placed near a water source so that you can connect it directly to your plumbing system.

Role Of Air Conditioner Evaporator Coil

The air conditioner evaporator coil is the most important part of your air conditioner.

It’s the heart of your home’s cooling system and works to pull heat out of your home and the air circulating throughout it.

Here are the key roles of the evaporator coil:

  • Heat Absorption: The primary function of the evaporator coil is to absorb heat from the surrounding air. When warm air is pulled into the air handler, it passes over the evaporator coil. The refrigerant under the coil absorbs the heat energy from the air, causing the refrigerant to evaporate and turn into a gas.
  • Cooling the Air: As the evaporator coil absorbs heat from the air, it cools the air passing over it. The cooled air is then circulated back into the room through the air conditioning vents, providing a comfortable indoor environment.
  • Humidity Control: Along with cooling the air, the evaporator coil also helps in dehumidification. As warm air passes over the cold evaporator coil, the moisture in the air builds up on the coil’s surface. This process removes moisture from the air, reducing humidity levels in the room.
  • Refrigerant Evaporation: The evaporator coil facilitates the evaporation of the refrigerant. When the refrigerant absorbs heat from the air, it evaporates from a liquid state into a gas. The refrigerant gas then flows to the compressor, where it gets pressurized for further processing in the air conditioning system.
  • Coil Frost Prevention: The evaporator coil is designed to maintain a temperature below the dew point of the incoming air. This prevents frost or ice formation on the coil’s surface. To avoid ice buildup, the air conditioner periodically goes through a defrost cycle, during which the flow of refrigerant is temporarily reversed, or the heating elements are activated to melt the accumulated ice.

7 Common AC Evaporator Coil Issues

We’ve all had the experience of being in a room that’s too hot, but we just can’t seem to cool it down. It’s like the air is just stuck—no matter how many fans or open windows you have, you’re still sweltering.

This is a common problem with evaporator coils, and it can be frustrating!

Here are some of the most common reasons why your AC evaporator coil isn’t working as well as it should:

Ice Buildup

This usually happens in the winter when the outdoor temperature is below freezing, but it can also happen during other seasons if your home is located in a colder climate. Ice buildup on your evaporator coil will make it hard for air to flow through the system, leading to poor performance and reduced energy efficiency.

Dirty Coils

When dust and debris get into your evaporator coils, they reduce their ability to cool your home efficiently. Dirty coils may also cause ice formation problems during cold weather because the moisture inside the unit will not evaporate as easily when dirt or other contaminants is blocking its path.

Coil Corrosion

Coil corrosion is a problem that occurs when the air conditioning system has a low refrigerant charge or leaks. This causes minerals in the water to build up and form rust on the evaporator coil.

Mold and Mildew Growth

Mold and mildew growth are caused by high humidity levels, which are caused by clogged drains, leaks in the system, or poor ventilation. It can also be caused by condensation that drips into your attic through missing insulation.

Coil Freezing

If your air conditioner is freezing, it’s probably because the coil inside is dirty or damaged. A dirty coil will reduce the efficiency of your air conditioner and make it work harder to cool your home. A damaged coil can cause water leaks and damage your ceiling or walls.

Coil Leaks

If your AC unit is leaking water, there could be many different causes, including a loose fitting on the drain tube, an improperly installed drain tube, or a broken pump in the condenser unit (outside).

Restricted Airflow

If you notice that your AC’s airflow is restricted or uneven throughout your house, it could be due to some type of obstruction in the ductwork (like a collapsed duct). One way to check for this problem is by blowing into one end of each register and seeing if air comes out at the other end (you should hear a whistling sound).

What Is A Condenser Coil?

A condenser coil is a device that helps to cool the air in your home. It’s made of metal and has a fan that draws air from inside the home, across the metal coils, and then back inside again. The coils are surrounded by refrigerant gas that cools down when it evaporates, then turns into a liquid when it contacts the cold metal. As this happens, heat is drawn out of the surrounding space and into the liquid refrigerant.

Role Of The HVAC Condenser Coil

The condenser coil plays a crucial role in the operation of an HVAC (Heating, Ventilation, and Air Conditioning) system. Here are the key roles of the AC condenser coil:

  • Heat Dissipation: The primary function of the condenser coil is to dissipate heat from the HVAC system. After the refrigerant absorbs heat from the indoor space in the evaporator coil, it carries the heat to the condenser coil. The condenser coil is located in the outdoor unit of the system. As the refrigerant flows through the coil, it releases the absorbed heat to the surrounding air or a heat sink.
  • Refrigerant Condensation: The condenser coil facilitates the condensation of the refrigerant. As the high-pressure, high-temperature refrigerant flows through the coil, it cools down due to the ambient air or the heat sink. The refrigerant condenses from a gas state into a liquid state during this process.
  • Pressure Reduction: The condenser coil also helps reduce the refrigerant’s pressure. As the refrigerant condenses, it undergoes a pressure drop, transitioning from a high-pressure state to a lower-pressure state. This pressure reduction prepares the refrigerant for the next stage of the cooling cycle.
  • Efficient Heat Transfer: The design and construction of the condenser coil are optimized for efficient heat transfer. The coil typically consists of multiple rows of refrigerant-filled tubes with fins or aluminum plates attached to them. This configuration maximizes the surface area available for heat exchange between the refrigerant and the surrounding air or heat sink, enhancing the heat dissipation process.
  • Outdoor Air Movement: The condenser coil is often accompanied by a fan or blower in the outdoor unit. The fan draws ambient air over the coil, promoting airflow and improving heat transfer. This air movement helps carry away the heat the condenser coil releases, aiding in the cooling process.

5 Common Air Conditioning Condenser Coils Issues.

There are a variety of common issues with air conditioning condenser coils. It’s important to identify these condenser coil problems and repair/fix them before they turn into major problems. 

Here are some common issues that you might encounter with your condenser coils:

1) Dirty or clogged condenser coils

2) Corroded plates on your condenser coils

3) Frozen condenser coils

4) Leaking refrigerant on your condenser coils

5) Broken capacitors or other parts inside your air conditioning unit

Difference Between Evaporator Vs. Condenser Coil

The HVAC system consists of two main components related to heat transfer: the evaporator coil and the condenser coil. Here’s a comparison table highlighting the key differences between the two:

AspectCondenser CoilEvaporator Coil
LocationOutdoor unitIndoor unit
FunctionReleases heat from the refrigerantAbsorbs heat from indoor air
DesignUsually made of copper or aluminum fins and tubesUsually made of copper or aluminum fins and tubes
Refrigerant FlowReceives high-pressure, high-temperature vaporReceives low-pressure, low-temperature vapor
Heat TransferTransfers heat to the outdoor airTransfers heat to the refrigerant
AirflowRequires good airflow for optimal performanceRequires proper airflow for efficient operation
MaintenanceRequires periodic cleaning of dirt and debrisRequires periodic cleaning to prevent mold growth
SizeTypically larger than the evaporator coilTypically smaller than the condenser coil
Coating ProtectionMay have a protective coating for durabilityMay have an anti-corrosion coating
Environmental ImpactReleases heat into the outdoor environmentHelps cool indoor air and improve energy efficiency

Evaporator and Condenser Coils Maintenance Tips 

The evaporator and condenser coils are the heart of your HVAC system. They work together to regulate the temperature of your home or office and help keep you comfortable all year long. While it’s important to have a professional HVAC technician inspect your coils every few years, there are numerous DIY things you can do on your own to keep them running smoothly.

Here’s a chart summarizing maintenance tips for the evaporator and condenser coils:

Maintenance TaskEvaporator CoilCondenser Coil
Cleaning FrequencyAnnually or biannuallyAnnually or more frequently, if in a dusty area
Cleaning MethodA soft brush or vacuum cleanerHose, soft brush, or coil cleaning solution
Air Filter MaintenanceRegular inspection and replacementRegular inspection and replacement
ClearanceEnsure proper clearance around the coilTrim vegetation and clear obstructions
Condensate Drain LineRegularly check and clear clogs
Coil Cleaning ProductsConsider using specialized coil cleaning products.
Bent Fin StraighteningInspect regularly and straighten bent fins.
Surrounding AreaClear debris and objects around the unit
Protection from DamageAvoid placing objects near the condenser unit
Professional MaintenanceConsider scheduling professional maintenance.

Consider Stay Cool Climate Control For All Your HVAC Needs!

If you’re dealing with issues with your evaporator and condenser coils, and don’t know where to turn, consider Stay Cool Climate Control for all your HVAC needs in O’Fallon, MO. 

Stay Cool Climate Control is a locally-owned and operated business that has been serving the O’Fallon community since 2019. We have a wide range of experience in all types of HVAC systems, from residential to commercial, so no matter your needs, we can help you find the perfect solution. We specialize in installing new or repairing existing systems, so if you seek a reliable company that can help you with everything about HVAC, look no further than Stay Cool Climate Control!

We are licensed, bonded, insured, and certified by many leading manufacturers in the industry. Our technicians are trained and experienced in troubleshooting complex problems and repairing any make or model of equipment.

If you need help with the following:

– Evaporator Coils

– Condenser Coils

– Air handler

– Heat Pumps

– Furnaces & Boilers

– A faulty thermostat or control board

– Faulty wiring

– Faulty ductwork (leaks)

– Air Conditioning Services and Solutions in O’Fallon

– Regular maintenance of HVAC

– Air Conditioning Repair

– Heating Repair

– Residential & Commercial Services

Our goal is to make sure that our customers feel comfortable and confident when they come to us with their problems so they can rest assured that they’ll get their issues fixed quickly and professionally—and without breaking the bank!

Whether your air conditioner is acting up during the hottest summer months or your furnace isn’t heating as well as it should during these frigid winters, we’re here for you 24/7, with emergency services available 365 days a year!

Call us today at (636) 542-8600 to schedule an appointment with our licensed and skilled HVAC technician in O’Fallon, MO!

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