Al’s Plumbing, Heating & A/C in Plano, Texas provides maintenance & repairs for all brands of Central A/C, Gas & Electric Furnace, and Heat Pumps.  Additionally we sell and install new HVAC Systems from American Standard (same company as Trane), Ameristar (same company as American Standard) and Coleman HVAC (same company as York HVAC).

Al’s also provides full service plumbing maintenance, repairs and replacements for every plumbing component in your home.  Al’s sells and installs Rheem Professional Series gas & electric water heaters, and tankless water heaters.  Al’s is near your home in Plano, Allen, and Frisco.  We service all homes in southern Collin and Denton Counties with no travel charges.

Call Al’s today to discuss any concerns or problems you have with your HVAC System or Plumbing.  We will arrange an appointment at your convenience and offer 24/7 Emergency Service.

Why The Indoor Cooling Coil (inside furnace) and Outside Air Conditioner Unit Freeze

Click Below To See A YouTube Video About Central A/C Freeze-Up.

An A/C Freeze Up Is Not Uncommon And Is Caused By:

• Too little air-flow through the HVAC system caused by dirty air filters
• Too little air-flow through the system caused too many air ducts closed
• Too little air-flow through the system caused by a dirty cooling / evaporator coil inside the furnace
• Low refrigerant level
• Thermostat set too low — below 68 degrees
• Faulty contactor in outside unit (causing it to keep running when it’s suppose to be off)
• Faulty fan (inside or outside)

• Dirty air filters reduce airflow.  Check & replace the air filter each month as needed.  If the filter looks dirty, it is and it needs replaced.
• Most or all of air-registers must be open for proper airflow.  Your HVAC (Heating, Ventilation, & A/C) system is designed to work with all the registers open, though it may be ok to close 1 or 2 vents.  If it’s a well designed system with well sealed ductwork, you can close up to two.  Closing more than two can result in your A/C running too cold and freezing due to too little airflow.  In winter, your gas furnace can run too hot and shut down to protect itself.
• Your A/C  “cooling-coil” (inside the furnace) gets dirty and must be cleaned occasionally for adequate airflow.
• Low refrigerant will cause a freeze up.  When refrigerant level gets low it is common for the indoor coil to freeze.   As the level gets lower and lower, the system will not cool properly, or stop cooling at all.
• Setting your A/C thermostat lower than 68 degrees can cause a freeze up.  As the indoor temp reaches 68 degrees, there is not enough heat in the air passing over the indoor cooling coil which causes it to get too cold and freeze.
• A faulty contactor in outside unit will cause freeze up because the outdoor unit keeps running when it should be off.
• The contactor’s purpose is to send electricity to the outside A/C unit.  As your thermostat calls for cooling, the contactor moves to connect to your A/C to electricity.  When the thermostat reaches the desired temperature, it tells the contactor to disconnect the electricity and the outside unit turns off.
• Faulty fans cause freeze ups.  There is a fan / blower inside the furnace and another inside the outdoor unit.  If either fan stops working, the system will likely freeze.

This YouTube video shows a frozen Cooling Coil (this coil is always located inside the furnace).  It shows how you can clean the cooling coil to increase air flow. A dirty cooling coil is one of the most likely reasons and a/c is freezing.

What To Do If Your A/C Freezes:

• Shut off the A/C off at the thermostat.
• Speed up the ice melting process by turning on the furnace fan with A/C turned off.
• Once the ice is melted, turn the air conditioner back on. It should start cooling your home immediately.
• It will freeze again until the problem is fixed.  If a very dirty air filter was replaced, that will likely have solved the problem.  If the filter was ok, call an HVAC Technician to diagnose the problem and repair it.

Al’s Plumbing, Heating & A/C in Plano, Texas provides maintenance & repairs for all brands of Central A/C, Gas & Electric Furnace, and Heat Pumps.  Additionally we sell and install new HVAC Systems from American Standard (same company as Trane), Ameristar (same company as American Standard) and Coleman HVAC (same company as York HVAC).

Al’s also provides full service plumbing maintenance, repairs and replacements for every plumbing component in your home.  Al’s sells and installs Rheem Professional Series gas & electric water heaters, and tankless water heaters.  Al’s is near your home in Wylie, Rowlette, & Garland.   We service all homes in southern Collin and Denton Counties with no travel charges.

Call Al’s today to discuss any concerns or problems you have with your HVAC System or Plumbing.  We will arrange an appointment at your convenience and offer 24/7 Emergency Service.