Ice forming on your air conditioning (AC) fan coil can be a common issue that affects the efficiency and performance of your cooling system. In this article, we will explore the reasons behind ice formation and step by step to fix the problem.

Step by step to fix aircon ice forming: 

Fixing ice formation on an air conditioner involves identifying and addressing the underlying issues causing the problem. Here are step-by-step instructions to help you troubleshoot and resolve the issue:

  • Turn off the AC:

As soon as you notice ice forming on your air conditioner, turn it off to prevent further damage and allow the ice to melt.

  • Inspect the Air Filter:

Check the air filter for dirt and debris. A clogged filter restricts airflow and can lead to ice formation. Clean or replace the filter if necessary.

  • Check for Refrigerant Leaks:

Inspect the refrigerant lines for any visible leaks. If you see signs of leaking refrigerant, such as oily residue, it’s crucial to address the leak and add refrigerant as needed.

  • Verify Refrigerant Levels:

Ensure that the refrigerant levels are within the manufacturer’s recommended range. Low refrigerant levels can lead to freezing. Consult a professional if you need to add refrigerant.

  • Inspect the Evaporator and Condenser Coils:

Examine the coils for dirt and debris. Clean them using a soft brush or vacuum cleaner. Dirty coils can hinder heat exchange and contribute to ice buildup.

  • Check for Airflow Issues:

Ensure that there are no obstructions around the air handler, and the vents are open and unblocked. Proper airflow is essential to prevent freezing.

  • Examine the Thermostat Settings:

Verify that the thermostat is set to a reasonable temperature. Avoid setting it too low, as it can lead to overcooling and ice formation.

  • Thaw the Ice:

Allow the ice to melt completely before attempting to restart the air conditioner. You can use fans or gently warm the coils with a hairdryer to expedite the melting process.

  • Schedule Professional Maintenance:

Consider scheduling a professional aircon maintenance service. An experienced technician can identify and address underlying issues, perform a thorough inspection, and ensure optimal performance.

  • Address Ductwork Issues:

Inspect the ductwork for leaks or blockages. Leaky ducts can result in a loss of cool air and may contribute to freezing. Seal any leaks and clear obstructions.

  • Monitor the System:

After addressing the issues, monitor the system to ensure that ice formation does not recur. If the problem persists, seek professional help to diagnose and resolve any more complex issues.

Reasons of Ice formation on AC unit:

The occurrence of ice formation on an air conditioner is a common issue that can disrupt the efficient functioning of the cooling system. Understanding the reasons behind the formation of ice on air conditioners is crucial for homeowners and HVAC professionals alike. In this exploration, we delve into the various factors that contribute to the puzzling phenomenon of ice buildup on air conditioning units. By unraveling these reasons, we aim to shed light on the mechanisms at play and provide insights into how individuals can prevent and address this issue, ensuring the optimal performance and longevity of their cooling systems.

  • Low Refrigerant Levels:

When your AC system has insufficient refrigerant, the evaporator coil temperature drops excessively, causing condensation to freeze and form ice.

  • Restricted Airflow:

Restricted airflow due to clogged air filters, blocked ducts, or closed vents can reduce the amount of warm air reaching the evaporator coil. This can lead to a drop in temperature and ice formation.

  • Dirty Evaporator Coils:

Accumulated dirt and debris on the evaporator coils can act as an insulator, preventing efficient heat exchange. This may cause the coils to become too cold, leading to ice formation.

  • Malfunctioning Thermostat:

A malfunctioning thermostat may lead to continuous operation of the compressor, causing the evaporator coil to become excessively cold and resulting in ice buildup.

  • Defective Blower Motor:

A malfunctioning blower motor can reduce the airflow over the evaporator coil, causing the coil temperature to drop and promoting ice formation.

How to Fix Ice Formation:

  • Check Refrigerant Levels:

Consult with a professional HVAC technician to assess and replenish refrigerant levels to the manufacturer’s specifications.

  • Ensure Adequate Airflow:

Regularly clean or replace air filters to maintain proper airflow. Check for and remove any obstructions in ducts and ensure that vents are open and unblocked.

  • Clean Evaporator Coils:

Schedule routine maintenance to clean the evaporator coils. This helps improve heat exchange efficiency and prevents ice formation.

  • Calibrate Thermostat:

If your thermostat is malfunctioning, recalibrate it or replace it if necessary. Ensure the thermostat is accurately reflecting the temperature in your living space.

  • Inspect and Repair Blower Motor:

Have a professional inspect and repair the blower motor if it’s not functioning correctly. This will ensure proper airflow over the evaporator coil.

In what ways does ice formation on an air conditioner significantly impact its performance?

Reduced Airflow:

Ice formation on the evaporator coils restricts the airflow, making it difficult for the air conditioner to effectively cool the air. This reduction in airflow can lead to insufficient cooling in your living space.

Inefficient Cooling:

When ice builds up on the coils, it acts as an insulator, preventing the coils from absorbing heat from the air. This insulation effect decreases the efficiency of the cooling process, causing the air conditioner to work harder to achieve the desired temperature.

Increased Energy Consumption:

The air conditioner has to work harder and longer to compensate for the reduced efficiency caused by ice buildup. This increased workload results in higher energy consumption, leading to higher electricity bills.

Strain on Components:

Ice formation can place additional strain on various components of the air conditioner, including the compressor. This increased stress may lead to premature wear and tear, potentially causing long-term damage to the system.

Risk of System Failure (Components damage)

If ice buildup is not addressed promptly, it can escalate and lead to more severe issues. Continued operation of the air conditioner with ice accumulation may result in system failure or damage to critical components.

Decreased Lifespan:

The continuous operation of an air conditioner with ice formation can contribute to a shorter lifespan for the unit. Regular occurrences of freezing and thawing can cause wear and tear on the system, reducing its overall longevity.

Uneven Cooling:

Ice forming on the air conditioner can result in uneven cooling or inadequate temperature control in your home. This can lead to discomfort for occupants, especially during hot weather when the cooling system is needed the most.

Excess water dripping:

As the ice on the evaporator coils melts, it can result in excess water dripping into the unit. This water can then cause damage to the interior components and potentially lead to issues like mold growth.


Regular maintenance for your AC, along with addressing issues like ice formation on the fan coil, plays a pivotal role in prolonging the life of your cooling system and enhancing its overall efficiency. If you’re unsure about handling these tasks, it’s recommended to enlist the expertise of a qualified HVAC professional for a comprehensive inspection and any required repairs.

SureCool Aircon Technicians excel in all types of air conditioner repair and services. Secure budget-friendly AC services with us. Book your appointment now at 90098748 (call/WhatsApp).