Air Comfort Services

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Signs Your HVAC has Frozen Coils

Top Signs To Look For If You ThinkYour HVAC Coils Are Frozen

How to Spot and Fix the Problem Before It Gets Worse

During the cold winters and humid summers in the Tri-Cities—from Johnson City to Kingsport and Bristol—your HVAC system works hard to keep your home comfortable. However, if your system isn’t performing as it should, you might be dealing with frozen coils.

Frozen HVAC coils are a common problem, and if left unchecked, they can lead to bigger issues like poor airflow, higher energy bills, and even system damage. In this blog, Air Comfort Services will walk you through the signs of frozen coils, what causes them, and when to call for professional help.

What Are HVAC Coils?

Your HVAC system has two types of coils:

  1. Evaporator Coils – Located inside your indoor unit, these absorb heat from your home.
  2. Condenser Coils – Located in the outdoor unit, these release the heat outside.

When the evaporator coils freeze, your HVAC system can’t circulate air effectively, leaving your home uncomfortable and potentially damaging the unit.

Signs of Frozen HVAC Coils

1. Reduced Airflow or Warm Air Coming from Vents

If you notice weak airflow or that your HVAC system is blowing warm air instead of cool air (in summer), frozen coils could be the culprit. When the coils are covered in ice, they can’t cool the air effectively.

? Quick Check: Hold your hand over a vent—if there’s little to no air coming out, frozen coils could be restricting airflow.

2. Visible Ice or Frost on the Coils or Refrigerant Lines

One of the most obvious signs is visible ice buildup on the indoor unit or refrigerant lines. Check your HVAC system:

  • Look for frost or ice on the evaporator coils (inside your air handler).
  • Check for ice on the copper refrigerant lines leading to the outdoor unit.

? Warning: Don’t try to chip away the ice—it can damage the coils.

3. Water Leaks or Pooling Around the Unit

As the ice on the coils begins to melt, it can overflow the drain pan and cause water to leak around the indoor unit. If you see water pooling on the floor, it’s a strong indicator of frozen coils.

4. Higher Energy Bills

Frozen coils force your HVAC system to work harder to maintain your desired temperature. This strain can lead to longer run times and increased energy usage, which you’ll notice on your utility bills.

5. HVAC System Frequently Turns On and Off (Short Cycling)

If your HVAC system is short cycling—turning on and off more frequently than usual—it could be struggling due to frozen coils. This issue not only makes your home uncomfortable but can also damage the compressor over time.

Frozen HVAC unit with Frozen Coils and Snow on ground

What Causes Frozen HVAC Coils?

Understanding the root causes can help prevent frozen coils in the future:

  1. Dirty Air Filters
    Clogged air filters restrict airflow, causing the coils to get too cold and freeze.
  • Solution: Replace your filters regularly—every 1-3 months.
  1. Low Refrigerant Levels
    Low refrigerant causes the coils to drop in temperature and freeze. This is often due to a refrigerant leak, which needs professional repair.
  2. Blocked or Closed Vents
    Closing too many vents or having blocked vents can restrict airflow, leading to frozen coils.
  • Solution: Keep vents open and clear of furniture or debris.
  1. Dirty Coils
    Dust and debris buildup on the evaporator coils can prevent proper heat transfer, causing the coils to freeze.
  • Solution: Schedule regular HVAC maintenance to keep your system clean.
  1. Thermostat or Fan Issues
    If your fan isn’t running properly or your thermostat isn’t cycling the system correctly, it can contribute to freezing.

How to Fix Frozen Coils

If you suspect frozen coils, here’s what you can do:

  1. Turn Off the System. Shut off your HVAC unit to prevent further damage and let the ice thaw.
  2. Check the Air Filter. Replace it if it’s dirty or clogged.
  3. Ensure Vents Are Open. Make sure airflow isn’t restricted by blocked or closed vents.
  4. Call a Professional. If the coils are still frozen after thawing, or if you suspect low refrigerant or mechanical issues, call the experts at Air Comfort Services.

Prevent Frozen Coils with Regular Maintenance

The best way to prevent frozen coils is through regular HVAC maintenance. At Air Comfort Services, we offer comprehensive tune-ups to ensure your system is running efficiently year-round.

? Benefits of Regular Maintenance:

  • Improved system efficiency and performance
  • Lower energy bills
  • Fewer unexpected breakdowns
  • Longer system lifespan

Call Air Comfort Services for Frozen Coil Repairs

If you suspect frozen HVAC coils in your Tri-Cities home, don’t wait—let our team at Air Comfort Services help! With over 20 years of experience serving Johnson City, Kingsport, Bristol, and surrounding areas, we’re your trusted HVAC experts for repairs, maintenance, and new installations.

? Call us today at (423) 677-7856 or schedule an appointment online!

? Proudly serving Johnson City, Kingsport, Bristol, Elizabethton, Gray, and surrounding communities.

Don’t let frozen coils leave you in the cold—trust Air Comfort Services to keep your home comfortable year-round!